I would like to know where are "all that apply" if only that is ok with you
The subordinate clause is "when the delivery man arrives" (option c.) because 1. it is introduced by "when" and 2. we can ask question to the main clause about this one.
The correct answer should be a.. the audience will become distracted.
Gesturing too much distracts audience which is why it is important to be calm as a speaker and use gestures only when needed to emphasize or persuade the audience. Too much of it and too repetitive makes the audience focus on them and not on the speech.
Answer:
Definitely your 3rd answer
Explanation:
"the community's position on this issue is clear; school uniforms would be an unwelcome change" implies that the school community was asked and they did not like the idea of uniforms. To make that more clear, you can add your third answer. It is also a fact, not an opinion, and fits well with your statements.
hope this helped :)