A few of the committee members DID NOT ATTEND.
simple predicate. This is the correct version. "Attend" is the main verb. As there is one verb , the predicate is simple. The verb says what the subject :a few of the committee member did not do: to attend the meeting.
These options are wrong:
-predicate adjective. In the given sentence, there is not any adjective in the predicate attached to the subject through "to be". For example, in this sentence: The committee members were tired. , the underlined word is a predicative adjective.
-predicate nominative. In the given sentence, there is not a noun in the predicate attached to the subject though the verb "to be". For example, in this sentence: It is Mrs Charlston. , the underlined word is a predicative nominative.
-complete predicate. In the given sentence, there are not two verbs. For example, in the sentence: The committee discussed and voted for a solution., the underlined verbs make up a complete predicate.