DA0-002 Visualization and Reporting Practice Question
A data analyst wants to visualize the distribution of employee salaries across departments and identify any outliers. Which chart type would best show quartiles, median, and potential outliers?
⚠ Common exam trap
DA0-002 often tests the confusion between histogram and box plot — candidates pick histogram because it 'shows distribution,' but only the box plot explicitly encodes quartiles, median, and outliers in one view.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Box plot
A box plot is purpose-built to display the five-number summary — minimum, first quartile (Q1), median, third quartile (Q3), and maximum — with whiskers extending to 1.5×IQR and individual points plotted beyond that as outliers. This makes it the ideal chart for comparing salary distributions across departments while simultaneously surfacing outliers. No other listed chart encodes quartiles and outliers in a single view.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Heat map
Why it's wrong here
A heat map encodes values as colour intensity across a two-dimensional matrix, so it cannot plot quartiles, median or individual salary outliers along a single numeric axis. It is tempting for spotting patterns in categorical cross-tabulations, but not for summarising one variable's distribution.
- ✗
Histogram
Why it's wrong here
A histogram bins one continuous variable into frequency bars, showing distribution shape but not the precise quartile boundaries or median value the analyst needs. It is tempting because it exposes skew and outliers, yet it lacks the explicit statistical markers a box plot provides.
- ✓
Box plot
Why this is correct
A box plot encodes the median, lower and upper quartiles, and whiskers, with points beyond the whiskers flagged as outliers. That five-number summary directly satisfies the requirement to show salary distribution spread and identify extreme values across departments.
- ✗
Scatter plot
Why it's wrong here
A scatter plot displays the relationship between two numeric variables as coordinate points, so it cannot render quartiles or a median line for one salary distribution. It is tempting because it reveals outliers visually, but that detection relies on correlation between paired variables, not a five-number summary.
Go deeper
Related to this question
About these practice questions
Courseiva writes every DA0-002 question from scratch — 1,004 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official CompTIA exam blueprint
This DA0-002 practice question is part of Courseiva's free CompTIA 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 DA0-002 exam.