When we wish to make an inference about a population, we typically take a smaller sample that we can make generalizations from. Let's say that we wish to estimate the average height of all college students in the USA. We do so by asking every woman in CDS 101 to fill out an anonymous online form where they can report their height. What problems might prevent our generalization from being an accurate estimate of the average height of the entire population? Select all that apply.

a. By only including women, we are not getting an accurate estimate of average height for our population of interest; therefore, we need to measure the men as well. b. It is impossible to get an accurate estimate of average height without taking a census of all college students in the USA. c. By looking only at students in CDS 101 at George Mason, we are taking a convenience sample rather than randomly sampling women from the whole population (all college students at all universities). d. Some students may not respond to the survey.