John deposited $10,000 to open a new savings account that

I have quite similar strategies as Mr Bunuel does, but with a little more detailed explanation.

Step 1:
4% interest on $10,000 per year (12 months). However, his account will receive profit after 3 months as it is on a compound interest basis. So let's find out the amount of interest after the first 3 months first:

(10000 x 4 x 3)
________________ = 100
(100 x12)

So, after 3 months his capital is 10000 (the original amount) + 100 (the profit) = 10100

Step 2:
In the second 3 months, he will earn a profit on the capital amount and also on the profit earned in the first three months.

So, the profit for the second 3 months is:
(10100 x 4 x 3)
________________ = 101
(100 x12)

In total, he receives a profit of 100+101 = 201
His capital was 10000
Therefore after 6 months, he receives 10000 + 201 = 10201
Answer D