I'm assuming that the underlined verb is bowling.
If that is the case, then the answer would be gerund.
Gerund is a verb form that functions as a noun in a sentence. As you can see here, bowling is used as the subject of the sentence.
Although present participle looks the same, it is used as an adjective, not a noun in a sentence. Since bowling is not a participle, it cannot be a participial phrase. Infinitive has the following form: to + verb.
