What is the infinitive phrase in this sentence?

In August, we went to Ontario and to upstate New York to see Niagara Falls.
A. to Ontario
B. to upstate New York
C. to see
D. to see Niagara Falls

I think its C

3 answers

That's an infinitive, but it's not an infinitive phrase.
So it would be D?
Yes. To see Niagara Falls is the infinitive phrase.