Answer:
c. Closing date
Step-by-step explanation:
No advertisement is accepted for the next edition after the Closing Date. For an ad to run after this date, the publisher has to issue written permission. Cancellations are also not accepted after this date. Unless otherwise agreed, clients are expected to make full payments for the ad by the end of the closing date.
The on-sale date is the day the issue is expected at the newsstand for customers to buy.