The nurse is assessing a pregnant woman in the clinic. In the course of the assessment, the nurse learns that this woman smokes one pack of cigarettes per day. Which of the following is the first step the nurse should take to help the woman stop smoking（）
A. Assess the client’s readiness to stop.
B. Suggest that the client reduce the daily number of cigarettes smoked by one-half.
C. Provide the client with the telephone number of a formal smoking-cessation program.
D. Help the client develop a plan to stop.