How should Bill proceed?

a$.)$He should respond to the office assistant's email by emailing a list of his own questions that he would like discuss at the interview.

b$.)$He should write formal, professional responses to the list of interview questions and email them to the office assistant before the interview.

c$.)$He should prepare informal, yet professional answers to the list of questions and be ready to discuss them at the interview.

d$.)$He should develop informal, casual responses to the interview questions so that when he discusses them at the interview, he appears easygoing.