please answer it with explanation, thank you!

The expression a)' + (a30-a,010) represents the expected present value of benefits under a life annuity issued to a life aged 30 with A) the first 10 payments guaranteed (B) less than 10 payments if the life dies before age 40 (C) no more than 10 payments if the life dies after age 40 (D) benefits payable contingent on death within 10 years