Answer:
The sentence contains a participle correctly punctuated.
Step-by-step explanation:
The sentence above contains a present participle phrase hiding in the brush. This participle phrase is present as it ends in -ing. Participle phrase often include objects and/or modifiers that complete the thought (the PP in the brush).
What is more, this participle phrase is correctly punctuated because it is separated from the rest of the sentence by means of a comma. Participle phrases always function as adjectives, adding description to the sentence. That is to say, the information they provide is not considered essential to complete the meaning of the sentence. This is why it is offset with a comma.