This LFCS practice question tests your understanding of essential commands. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A user needs to view the contents of a large text file one screen at a time. Which command is best for this?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "best"
Why it matters: Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.
Clue: "which command"
Why it matters: Tests specific CLI syntax. Recall the exact command and its required context — near-synonyms and partial matches are common distractors.
nl file.txt
Why wrong: nl numbers lines but does not paginate output.
more file.txt
Why wrong: more is a pager but less is more feature-rich and commonly preferred.
cat file.txt
Why wrong: cat outputs the entire file at once, which is not suitable for large files.
less file.txt
less is a full-featured pager that allows scrolling up and down.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
less file.txt
Option D is correct because `less` is a terminal pager that allows forward and backward navigation through a file, making it ideal for viewing large text files one screen at a time. Unlike `more`, `less` supports scrolling both up and down, and it does not load the entire file into memory, which is efficient for large files.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
nl file.txt
Why it's wrong here
nl numbers lines but does not paginate output.
more file.txt
Why it's wrong here
more is a pager but less is more feature-rich and commonly preferred.
cat file.txt
Why it's wrong here
cat outputs the entire file at once, which is not suitable for large files.
less file.txt
Why this is correct
less is a full-featured pager that allows scrolling up and down.
Clue confirmation
The clue words "best", "which command" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
The trap here is that candidates often confuse `more` and `less` because both display content one screen at a time, but `less` is the more powerful and recommended tool for interactive viewing, and the LFCS exam expects you to know that `less` is the best choice for this task.
Trap categories for this question
Command / output trap
nl numbers lines but does not paginate output.
Detailed technical explanation
Under the hood, `less` uses the `termcap` or `terminfo` database to handle terminal capabilities and supports features like searching with `/` and `?`, jumping to line numbers, and following file growth (like `tail -f`). A subtle behavior is that `less` can read from stdin when no file is given, and it uses the `LESS` environment variable for default options (e.g., `-N` for line numbers). In real-world scenarios, `less` is preferred over `more` for log file analysis because it allows reviewing previous output without re-running the command.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A practitioner preparing for the LFCS exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Essential Commands — study guide chapter
Learn the concepts, then practise the questions
Essential Commands practice questions
Targeted practice on this topic area only
All LFCS questions
513 questions across all exam domains
Linux Foundation Certified System Administrator LFCS study guide
Full concept coverage aligned to exam objectives
LFCS practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise LFCS questions linked to User and Group Management.
Practise LFCS questions linked to Operation of Running Systems.
Practise LFCS questions linked to Essential Commands.
Practise LFCS questions linked to Networking.
Practise LFCS questions linked to Service Configuration.
Practise LFCS questions linked to Storage Management.
Practise LFCS questions linked to LFCS fundamentals.
Practise LFCS questions linked to LFCS scenario.
Practise LFCS questions linked to LFCS troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Essential Commands — This question tests Essential Commands — Read the scenario before looking for a memorised answer..
The correct answer is: less file.txt — Option D is correct because `less` is a terminal pager that allows forward and backward navigation through a file, making it ideal for viewing large text files one screen at a time. Unlike `more`, `less` supports scrolling both up and down, and it does not load the entire file into memory, which is efficient for large files.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Yes — watch for: "best", "which command". Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jun 25, 2026
This LFCS practice question is part of Courseiva's free Linux Foundation certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the LFCS exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.