Tech SkillsCore Concepts

Image Container Question Explained

This worked Docker Fundamentals practice question tests Core Concepts. Try the answer first, then review why A is the best choice.

Short answer

The correct answer is A. A container is a running instance of an image.

An image is the packaged filesystem and metadata. A container is a runnable instance created from an image. The key is to match the exact action in the prompt to the tool, command, or concept that performs that action directly. Here, A. A container is a running instance of an image is the only option that satisfies the scenario without adding unrelated behavior.

The Question

What is the relationship between an image and a container?

AA container is a running instance of an imageCorrect
BAn image is a running instance of a container
CThey are identical names for the same thing
DA container stores only Docker Hub passwords

Why A is correct

An image is the packaged filesystem and metadata. A container is a runnable instance created from an image. The key is to match the exact action in the prompt to the tool, command, or concept that performs that action directly. Here, A. A container is a running instance of an image is the only option that satisfies the scenario without adding unrelated behavior.

Why the other options are wrong

Option B: An image is a running instance of a container

Option B does not match the requirement in the prompt. The correct answer is A because An image is the packaged filesystem and metadata. A container is a runnable instance created from an image.

Option C: They are identical names for the same thing

Option C does not match the requirement in the prompt. The correct answer is A because An image is the packaged filesystem and metadata. A container is a runnable instance created from an image.

Option D: A container stores only Docker Hub passwords

Option D does not match the requirement in the prompt. The correct answer is A because An image is the packaged filesystem and metadata. A container is a runnable instance created from an image.

Key idea: Core Concepts

Core Concepts questions test whether you can connect a common workflow problem to the right practical command, service, or concept. Instead of memorizing isolated definitions, look for the job being done in the prompt: staging a file, querying rows, running code, persisting container data, checking a service, or choosing the right cloud building block. The best answer usually names the simplest tool that performs that job directly. For Docker Fundamentals, the safest study pattern is to read the scenario, underline the action verb, and eliminate answers that solve a different problem. If an option sounds related but changes the scope, adds risk, or describes a different layer of the stack, it is probably a distractor. After choosing an answer, explain why the other three fail; that habit builds the practical judgment these quizzes are meant to measure.

Ready to test the full skill?

Take the free Docker Fundamentals quiz and find the exact basics to review next. No signup required.

Practice related questions

Same skill area or adjacent concept. Use these after reviewing the explanation.

Related Docker Fundamentals Practice Questions