单项选择题A. There is no need to include sex in medical research. B. Sex should be taken into account in medical research. C. Sex will sometimes affect the medical research results. D. Different sexes do not influence the medical research results.

单项选择题A. The man likes to go to small concerts. B. The man likes to go to the concerts held in the big stadium. C. The man likes to go to big concerts where he can use binoculars. D. The man likes to go to the concerts where are many spectators.