Read the sentence:

it was a secret selection made by the leaders of the community the committee of elders who took the responsibility so seriously that there were never even any jokes made about assignments.

which of the following sentences correctly uses commas to mark the nonessential appositive phrase in this sentence?

a. it was a secret selection made by the leaders of the community, the committee of elders, who took the responsibility so seriously that there were never even any jokes made about assignments.

b. it was a secret selection, made by the leaders of the community, the committee of elders who took the responsibility so seriously that there were never even any jokes made about assignments.

c. it was a secret selection, made by the leaders of the community the committee of elders, who took the responsibility so seriously that there were never even any jokes made about assignments.

d. there is no appositive phrase in this sentence.