Olivia wants to learn a foreign language. To get an idea of how satisfied other students were after taking a foreign language course, she decides to take a random sample of 20 students. If Olivia randomly selects one class among all the foreign language classes taught that year, and then interviews all students in that class, the sampling method is a:

Cluster sampling method

Step-by-step explanation:

Cluster sampling is accomplished by dividing the population (students taking foreign language courses) into groups ( in this case different foreign course classes).

The groups are randomly selected (any of the foreign course class), and each element (student) in the selected clusters (class) are interviewed