Identify the italicized word or phrase.

The president is about to "speak".

participle

infinitive

verb phrase

The answer is: infinitive.

An infinitive verb does not possess any inflection that indicates a particular tense. It usually follows "to."

The rest of the options are incorrect because the participle of speak is spoken and a verb phrase contains a main verb, or a main verb plus auxiliaries or modal verbs. The verb in a verb phrase indicates the type of clause, such as declarative or imperative.

The answer is:

Infinitive