Final answer:
The nurse should administer the medication at 9:00 a.m. as scheduled.
Step-by-step explanation:
The nurse should administer the medication at 9:00 a.m., which is the time specified in the question. Option b)10:00 a.m., would be too late because it is an hour after the scheduled time. Option a)8:30 a.m., would be too early as the medication is supposed to be given at 9:00 a.m. Options c)11:00 a.m., and d)12:00 p.m., are even later and would deviate further from the scheduled time.