You didn't underline anything, so we cannot know for sure what the correct answer is. However, I'll just write down the entire infinitive phrases in these sentences, and you can see the answer based on that:
1. to see a great play
2. to cheer good plays
3. to practice until you know all the plays
The paragraph contains sentence variety
Here is the sentence using the words capacity and regulation:
The capacity of the hall can only accommodate at most 500 people; therefore, strict regulation of the flow of the people going in and out must be observed all the time. Regulation means control or management. Capacity means the amount or size that something can contain. Hope this answer helps.
Your answer is C, in the past.
Field trips are indeed valuable since they encourage students to interact with content in a number of ways. Students who struggle with conventional learning should feel smart and comfortable when concepts are expressed in a variety of media and modalities.