Answer:
- the axen (do you mean oxen?)
- The church choir
- the mob
- fleet of luxury cars (or just cars)
- clump of trees (or trees)
- a troupe of dancers (or just dancers.)
Step-by-step explanation:
As you probably know, a noun is a person, place, or thing (or idea), and the question is asking for you to underline the collective nouns, a word which here means acting as a group or a group of something, so we would underline the nouns which have a group in them.
Let me know if this helps!