B. he
The word 'he' is being modified by the participial phrase.
The word 'laughing' is the participle.
A PARTICIPLE is a verbal that is used as an adjective and most often ends in -ing or -ed. They express an action or a state of being. However, since they function as adjectives, participles modify nouns or pronouns.
A PARTICIPIAL PHRASE <span> is a group of words consisting of a participle and the modifier(s) and/or (pro)noun(s) or noun phrase(s) that function as the direct object(s), indirect object(s), or complement(s) of the action or state expressed in the participle.
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D. Students acting the parts of prisoners and guards
The answer is: <span>an educated guess or logical assumption based on available information.</span>
