Explanation:

- We're dealing with compound interest, where the amount grows due to interest that is calculated on the initial principal and previously accumulated interest.

- The principal grows to Rs35,680 in 3 years and Rs53,520 in 6 years.

- We need to find the compound interest for the first 3 years.

- The compound interest can be found by subtracting the principal from the amount after 3 years.

- By reverse calculating, we find the principal (P), targeted through the compound interest formula after 3 years.

- Amount after 3 years (Rs35,680) minus principal gives the compound interest.

- Given options are:

- Option 1: Rs11,983

- Option 2: Rs11,893

- Option 3: Rs10,842

- Option 4: Rs11,938

- After calculation, the compound interest is closest to Option 2: Rs11,893.

Therefore, the compound interest is correct with Option 2.