Group Research Designs Are Appropriate for Which of the Following

Group research designs are appropriate for which of the following?

A) Answering research questions about a single element, such as one person, one family, one organization, or one community.
B) Answering research questions that deal with groups of elements, such as people, organizations, and agencies.
C) Answering research questions that involve words or images rather than numbers and "counting things."
D) Answering research questions that include more than one independent variable.