What Is the Justification for the Decreasing Term Life Rider

What is the justification for the decreasing term life rider as part of the retirement income annuity?

A) If the annuitant dies before retirement, the beneficiary will receive annuity payments and the death insurance payments.
B) If the annuitant does before retirement, the premiums are refunded to the survivor
C) If the annuitant retires early, the premiums will pay for out of pocket expenses until benefits start
D) If the annuitant chooses not to retire, the annuity will expire.