What is a fully insured defined benefit plan?

A$)$

A plan that is funded entirely by life insurance and$/$or fixed annuity contracts, per IRC Section $412($e$)(3)$

B$)$

A plan that regularly buys married put options

C$)$

As a defined contribution plan, a fully insured plan is not insured by the Pension Benefit Guaranty Corporation $($PBGC$)$

D$)$

A plan fully supervised by the state insurance commissioner