I nees help with infinitive phrases and if it is a noun, adj., or adv. My question is:

Question

The political prisoner refused to denounce his principles.

Answer 1

The infinitive phrase is to denounce his principles.

This phrase answers "what" after renounce. That means the phrase is a direct object. What part of speech is a direct object?

Answer 2

Is it a noun?

Answer 3

Yep. This infinitive phrase is a noun.