Answer:
A
Explanation:
In 2 months, he got 70 stamps, meaning 35 stamps per month. On the first month, he has 55 stamps by the end of the first month, and since every month he gets 35 stamps, He was given 20 Stamps to start with. It is not D since he saves 35 stamps himself every month, meaning from the beggining of that month, he had 20, and by the end had 55, since the question specifies it shows the amont of stamps at the END of the month.