What should you do first when you are prewriting a biography?
a. identify a subject and generate questions for research
b. select a person and begin writing everything you know about him/her
c. create a timeline of the things that happened in the subject's life
d. read some biographies to get a feel for how to write one yourself

A 
if you use cross elimination, you will be able to see why.
B is incorrect because biographies require research
c is incorrect because you cant create a timeline without first doing research
d is incorrect because its biogrpahy is seperate from others. It about a different person and their life. Biogrpahies are independent. 
A is correct becuase you are doing research, you cant write about something you dont know! 

Hey perhaps you should add the passage? then we'll be able to you! : )