The correct answer to the question presented above would be letter d. to invite; party. The infinitive phrase and the last word of the infinitive phrase in the sentence would be 'to invite; party'. All the other choices do not match the correct answer.
In the sentence: Karissa wanted to invite up to fifteen
people to the party.
The infinitive words of the last word of the infinitive
phrase are D.to invite party rather ‘to invite up to fifteen people’.
Infinitives starts with the connective ‘to’.
