SAT Question f890dc20: Distributions, Center & Spread answer and explanation with Desmos solution

Choice B is correct. When a data set has an odd number of values, the median can be found by ordering the values from least to greatest and determining the value in the middle. Since the values are already presented in order from least to greatest and there are $7$ values, the median is the fourth value in the list. Therefore, the median is $3$.