What Are Valid Reasons for Selecting an Exploratory Sequential Strategy

What are valid reasons for selecting an exploratory sequential strategy research design?

A) The researcher is interested in both the relative occurrence of a phenomenon and the meanings ascribed to it.
B) On a two-person research team, each researcher is schooled in either qualitative or quantitative research methods.
C) There is little known about the topic, yet the researcher wants to be able to perform hypothesis testing.
D) The researcher is concerned that collection of quantitative data may bias data collected qualitatively.
E) The researchers expect to collect quantitative and qualitative data all at once.