Which committees are made
up of both House of
Representatives and
Senotors?

The joint committees are made up of both senators and representatives. They typically have an oversight or policy role but no legislative duties.

there are no options provided but you can choose among the following gender-neutral pronouns: zir, hir, eir, vis, tem, eir.

in the normal course of maintaining a pronoun-antecedent agreement, we could have used the words his or her but since we are also required to use gender-neutral language, we need to replace it with its equivalent gender-neutral pronoun.