Final answer:
The sentence containing a participial phrase is 'Exploring the cave, we found many unique creatures.' The phrase 'Exploring the cave' acts as an adjective, modifying 'we' by providing more details about the action taken.
Step-by-step explanation:
A participial phrase is a group of words consisting of a participle and the modifier and/or noun phrase it modifies, and it acts as an adjective. In the student's options, the sentence with a participial phrase is 'Exploring the cave, we found many unique creatures.' The phrase 'Exploring the cave' begins with a present participle ('Exploring') and modifies the pronoun 'we,' providing more information about what 'we' were doing. A key characteristic of a participial phrase is that it provides descriptive detail to a noun, much in the same way an adjective would.
In contrast, the other sentences do not contain participial phrases. Instead, they include simple predicates and direct objects without additional descriptive phrases that begin with participles.