This question is incomplete, here´s the complete question.
Identify the italicized phrase as a participial, gerund, infinitive, or appositive phrase.
The children, fascinated by the clown, did not want to leave the circus tent.
Answer: Infinitive
Step-by-step explanation:
The to-infinitive is used after a large list of specific verbs, especially the ones that express thinking and feelings, like 'choose', 'remember' and 'want', such as in this example.
Other examples with the same word could be:
Rose wants to help her aunt with the new computer.
The boss wanted to develop a new project.