Estavan Received a Questionnaire in the Mail Asking About His

Multiple Choice

Estavan received a questionnaire in the mail asking about his general buying habits.He was asked to identify the specific products that he typically buys,and the amount of each product that he typically uses.Which type of research will Estavan have taken part in if he completes the questionnaire and returns it

A)  archival research 
B)  naturalistic observation 
C)  survey method 
D)  case study approach