问题详情

Research into the reasons for friendship is thought to be unnecessary because ______.
A．it is only possible if a wide variety of experts are employed
B．it is too complex a subject to be scientifically investigated
C．no one has any difficulty in making friends
D．we believe we are capable of dealing with it ourselves此题为多项选择题。请帮忙给出正确答案和分析，谢谢！