问题详情

Whatwerethepeopleaskedtodointhestudy？
A．Tomakeafaceateachother.
B．Togettheirfacesimpressive.
C．Toclassifysomefacepictures.
D．Toobservetheresearchers"faces.
请帮忙给出正确答案和分析，谢谢！