Question

The following sentence contains _____.

To win an argument is seldom a desirable goal.
an adverbial prepositional phrase
an infinitive phrase as an adverb
an infinitive phrase as the subject

Answer 1

The answer is: [C]: "an infinitive phrase as the subject" .
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The infinitive is: "To win" .
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The infinitve phrase is: "To win an argument" .
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Answer 2

An infinitive phrase as the subject

Step-by-step explanation:

Infinitives are a type of verbals (verbs forms that do not act as verbs) that function as adjectives, adverbs or nouns in a sentence.

It is formed with the word "to" + the simple present form of a verb; for example, to + play. Infinitive phrases, then, are phrases containing an infinitive that is followed by any objects, and/or modifiers of that infinitive.

The sentence "To win an argument is seldom a desirable goal" contains an infinitive phrase, which it's "To win an argument", and such phrase is acting as a noun, more specifically, as the subject of the sentence because it is the main thing being described.