Jean is planning to take a foreign-language class. to research how satisfied other students are with their foreign language classes, she decides to take a sample of 50 such students. the university offers classes in five languages: spanish, german, russian, french, and japanese. she will select a random sample of 10 students from each language. what best describes the sampling technique jean is using?
a) a simple random sample
b) a stratified random sample
c) a voluntary response sample