Candidates for depth interviews could include a. current customers. b. members of the target market. c. executives and managers of the company. d. All of these are candidates for depth interviews.

d. All of these are candidates for depth interviews.

Explanation:

Depth interview is a research technique which is qualitative and involves conducting individual interviews which are very intense with the respondents in order to have their idea regarding certain topics or issues.

Candidates for depth interviews could include current customers, members of the target market and the executives and managers of the company. Therefore, all of these are candidates for depth interviews.