Annual income of Mason is 70,000 dollars.
He saves 7% of his annual earnings into a saving account.
So, his savings would be 7% of 70,000 = 0.07 x 70,000 = 4,900 dollars.
The saving account gives an interest rate of 3% per annum.
So the interest accrued on 4900 dollars over the year would be 3% of 4,900 = 0.03 x 4,900 = 147 dollars.
Total amount in the saving account would be sum of principal amount and interest accrued.
Total balance = principal amount + interest accrued.
Total balance = 4900 + 147 = 5,047 dollars.
Hence, option C is correct i.e. 5,047 dollars.