DA0-002 Data Concepts and Environments Practice Question
A hospital's data team is cataloging its data assets. They need to classify the blood type field stored for each patient (e.g., A+, O-). Which data type classification best describes this field?
⚠ Common exam trap
The trap here is assuming that because blood types contain letters and symbols, they represent a ranked or measurable scale rather than unordered labels.
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
✓
Nominal
Blood type is a categorical label that identifies which of the recognized blood groups a patient belongs to. There is no inherent order among A+, O-, AB+, and B-, and no arithmetic can be meaningfully performed on these values. Nominal classification is the only correct choice because it groups data into unordered, distinct categories.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Nominal
Why this is correct
Blood type values such as A+, O-, and AB+ are labels that identify categories with no inherent order or ranking. Nominal data classifies items into distinct groups where no category is greater or lesser than another. Because blood types cannot be meaningfully ordered or mathematically averaged, classifying them as nominal is correct for this hospital scenario.
- ✗
Interval
Why it's wrong here
Interval data has ordered values with equal distances between them, such as temperature in Celsius. Blood type categories have no measurable distance between them, so interval classification is inappropriate. Assigning numeric codes to blood types and treating them as interval would produce meaningless statistics like average blood type values.
- ✗
Ordinal
Why it's wrong here
Ordinal data has a meaningful order, such as pain scale ratings from 1 to 10 or education levels. Blood types have no natural ranking, so treating them as ordinal would incorrectly imply that A+ is somehow greater or less than O-. This misclassification would corrupt any ordering operations performed on the field.
- ✗
Ratio
Why it's wrong here
Ratio data has all the properties of interval data plus a true zero, such as weight or height. Blood types cannot be measured on a continuous scale with a meaningful zero point. Classifying this field as ratio would enable nonsensical calculations such as doubling a blood type or computing ratios between two patients' blood types.
About these practice questions
One of 1,004 original DA0-002 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. 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.