Some Research Is Likely to Be Quite Expensive While Other

Multiple Choice

Some research is likely to be quite expensive while other research can be conducted with few costs.Of the following,which study design is likely to be the least costly?

A) using available data from a library
B) distributing a mail questionnaire once to a convenience sample
C) a multi-site investigation conducted over a period of several years
D) in person interviews
E) focus groups