doctor order is to give a drug to the patient q.i.d., the best times to give this drug is at like schedule

doctor order is to give a drug to the patient q.i.d., the best times to give this drug is at like schedule:
a. 6am-12pm-6am-12pm
b. 3am-9am-3pm-9pm
c. 6am-2pm-10pm
d. 6 am -6pm