When Interviewing a Newly Admitted Client,the Nurse Learns That the Client

When interviewing a newly admitted client,the nurse learns that the client is a cigarette smoker.It is determined that the client has a 50 pack-year history.This means that the client has smoked:

A) 2 packs of cigarettes a day for 25 years
B) 50 cigarettes a week for the last year
C) 1 pack a week for the last year
D) 50 packs within the last year