Final answer:
In the sentence, the phrase 'Encountering a bear and its cub' is the gerund phrase. A gerund phrase consists of a gerund and any objects or modifiers of it. 'Encountering' functions as the gerund here.
Step-by-step explanation:
In the sentence provided: 'Alaskan brown bears are known to be fierce and protective parents. Encountering a bear and its cub could be dangerous, and hikers should be particularly cautious.' The phrase 'Encountering a bear and its cub' is the gerund phrase. A gerund phrase consists of a gerund (which is a verb ending in '-ing' that functions as a noun) and any modifiers or objects associated with it. In this case, 'encountering' is the gerund, and 'a bear and its cub' is the object of the gerund.
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