An instrument used for measuring a sample of behavior is:

A test is a systematic procedure for observing and describing one or more characteristics of a person, often by presenting a set of standardized questions or tasks to measure a sample of their behavior or knowledge. It is the instrument used to gather data.

• Measurement (B) is the process of assigning numbers to observations, often using a test.
• Assessment (C) is a broader term encompassing the entire process of gathering and interpreting information about student learning, which may include tests, observations, and portfolios.
• Evaluation (D) is the process of making judgments about the value or worth of something based on assessment data.