This question requires identifying a metaphor among the options. A metaphor directly states that one thing is another, unlike a simile which uses 'like' or 'as' for comparison. The correct answer is C, 'He is a lion in battle,' because it directly compares the person to a lion without using 'like' or 'as'. Option A is personification, not a metaphor. Option B is a simile, and option D is also a simile, making them incorrect.