Step 1: Understanding the statements.
- Frequency distributions are graphs that help us visualize how test scores are distributed across different values.
- The normal probability distribution is a theoretical distribution that shows how test scores are expected to be spread in a population. It is particularly useful in understanding how common or rare certain test scores are.
- Central tendency measures, such as mean, median, and mode, are numerical tools used to determine the center or middle of a distribution.
- Measures of variability, such as range, variance, and standard deviation, are numerical tools used to understand how spread out the test scores are within a distribution.
Step 2: Analyzing the options.
- (A) Incorrect, frequency distributions are graphs, but this option has an incorrect phrasing ("are graphs" should be clarified to mean that they are tools for representing the distribution).
- (B) Correct, normal probability distribution is a fundamental concept in statistics, used to describe how test scores are distributed.
- (C) Correct, central tendency measures help in understanding the central point in a set of test scores.
- (D) Correct, measures of variability explain how dispersed or spread out the scores are from the central value.
Step 3: Conclusion.
The correct answer is (B), (C), (D).