To Save Time, You Assign the First Fifty People Who

To save time, you assign the first fifty people who sign up to participate in your study to the experimental condition and the next fifty to the control condition. The interpretations you could draw from the study will be severely limited because

A) you needed to carry out a within-subjects design.
B) you failed to use random assignment to conditions.
C) you did not have enough participants to conduct your study.
D) you need to include another control condition to draw accurate conclusions.