Answer:
Metaphor.
Step-by-step explanation:
As per the question, the given sentence 'dad is a bear' employ metaphor as it establishes an implied comparison between the two completely distinct and unrelated things('dad' and 'bear'). This comparison is employed to describe and explain the audience about the similarity in characteristics of the person('dad') and the ('animal'). It assists in explaining the meaning more clearly. Thus, metaphor is the correct answer.