The correct option is B he found nothing wrong with me
Option A is the correct answer. The statement of the option justifies the use of the conjunction however in the sentence. Options B,C and D are also incorrect for the same reason. They all negate the use of the word, which denotes something contradictory to the situation happening in the sentence. Thus, the doctor having examined someone would more often than denote some kind of results leading to ill health. The use of however in the sentence means that something else has occurred, thus making option A the correct answer.