The correct option is B Resembles
Let’s examine the sentence: “He is resembling his father.” The sentence states the fact of resemblance as a forever truth and as an activity happening and continuing in the present. So, the correct tense for the sentence should be simple present tense and not in present continuous tense as used in its present construction. So, the present continuous tense of the sentence should be changed to simple present tense to improve it. Therefore, the improved version of the sentences is, “He resembles his father.” Hence, Option C is the correct answer.