Final answer:
July and August each have 31 days because of honors bestowed upon Roman Emperors Julius Caesar and Augustus Caesar, with the latter ensuring August matched July's length to maintain the appearance of equal importance. The correct option is A.
Step-by-step explanation:
The reason why July and August both have 31 days is related to Roman Emperors. In 46 BC, Julius Caesar introduced the Julian calendar, which is similar to our current calendar with 12 months and a leap year system. After Caesar’s death, the 5th month was renamed July in his honor.
Augustus Caesar, his successor, later had the month following July named after him as August. To avoid being seen as inferior to Julius, Augustus ensured that August also had 31 days, matching the length of July.
Hence, Option A is correct.