Scientists are creating vaccinations that prevent people from getting bird flu. If the virus mutates, a new vaccine needs to be made. The vaccine needs to be tested, which can be dangerous. It also takes a long time for scientists to know whether the vaccine works.
I really think it was Wundt. Not 100% sure though
I believe the answer is C. This is because most men do naturally have more muscle mass, so they need more energy to function. This is not the case if you do a lot of muscle building activities, though.
