Ben growled when i walked into his room. he barked at me to close the door as he lumbered back to his desk. he is such a bear in the morning! which figure of speech does the author use in the passage? a. simile b. extended metaphor c. personification d. epic simile

I believe the answer is B, an extended metaphor. 
It can't be A because similes are comparing two unlike things using the words "like" or "as", which will also eliminate D.
It can't be C because a personification is where an inanimate object is given human-like qualities. 

Throughout the entire passage, the author compares Ben to a bear and uses words such as "growled", "barked", "lumbered" which shows how the comparison between the two is prolonging throughout the passage.