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A verbal is a form of a verb that does not act as one. For example, if you say that you like swimming, the word swimming is the verbal because it comes from a verb but it is used as a noun because it is the act of swimming.
There are three types of verbals: infinitives, gerunds, and participles.
An infinitive is a word in its dictionary form, usually preceded by the word "to". I want to learn to cook. In this sentence, to cook acts as more of a noun than a verb, because the main verb is "I want", and "to cook" acts as more of a noun because that things is what you want. An infinitive can be used as a noun, adjective, or adverb.
A gerund is a verbal that has the suffix -ing and usually acts as a noun. With "I like swimming", swimming is the gerund.
A participle is a verb used as an adjective, such as flaming passion, enticing look, etc.
The only verb in our sentence is "to skydive". We see that this is an infinitive because it is preceded by the word "to". This means it is either a noun, adjective, or adverb. All goals are nouns. If your goal is to skydive, skydiving is a thing, making it a noun.
Therefore, the answer is A. It is used as a noun.
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