Final answer:
Mrs. Whatsit had the form of a star before being human. Option A is the correct answer.
Step-by-step explanation:
The correct answer is A) A star.
In the story mentioned in the question, Mrs. Whatsit is described as having had a different form before being human. One of the descriptions of Mrs. Whatsit compares her to a bird - "kind of like a bird herself-real sweet and pretty, but kind of timid and fluttery."
However, the question specifically asks about her form before being human. The answer can be found in the same paragraph that mentions the bird comparison, it says "How she did change." This suggests that Mrs. Whatsit was not a bird prior to being human.
Another clue can be found in the answer choices provided - a star, a dragon, and a flower. Out of these options, a star is the most likely form Mrs. Whatsit had before becoming human.
So Option A is the correct answer.