It's Fuerte for man and woman same as one person or other but if you have multiple-choice and is not in there then it has to be Fuertoso singular and for plural fuertes or fuertosos. they are less common do.
Hope I had helped.
Actually the correct answer is D. tendrá. Because A would be if you were talking about yourself. B would be if you were taking about a group including yourself, and C would be right if you were talking about a group not including yourself.