Which of the Following Statements Is True About Medical Examinations

Which of the following statements is true about medical examinations and inquiries?

A) A company may require applicants to take a drug test even before a conditional job offer has been made.
B) A preemployment health checklist can be required of applicants before a job offer is made, but physical medical exams cannot be requested until a job has been conditionally offered.
C) A drug test is considered a medical exam and cannot be administered unless a conditional job offer has been made.
D) Companies may ask questions about an applicant's current medical condition but not about past medical problems, even after a conditional job offer has been made.