Gains and losses can occur with pension plans when: A) Either the PBO or the return on plan assets turns out to be different than expected. B) Either the ABO or the return on plan assets turns out to...

A) Either the PBO or the return on plan assets turns out to be different than expected.

B) Either the ABO or the return on plan assets turns out to be different than expected.

C) Either the PBO, the ABO, or the return on plan assets turns out to be different than expected.

D) Either the PBO or the ABO turns out to be different than expected.