Final answer:
The verbal phrase in the sentence 'Alice, frightened by the siren, covered her ears.' is 'Frightened by the siren'. It acts as a participial phrase modifying the noun, Alice.
Step-by-step explanation:
The sentence in question is: Alice, frightened by the siren, covered her ears. In this sentence, the verbal phrase is A. Frightened by the siren. A verbal phrase is a verb form used as some other part of speech in a sentence. In this case, frightened by the siren is acting as an adjective, modifying the noun, Alice. This type of verbal phrase is known as a participial phrase. The options B, C, and D are not valid as none of them serve as verbal phrases in the given sentence.
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