问题
选择题
The government officials met the workers and engineers working on the stadium, most____ were migrant workers．
A．of which
B．of who
C．of whom
D．of them
答案
答案：C
考查非限制性定语从句，先行词为the workers and engineers，他们中的大多数应用most of whom，句意：政府的官员在体育馆见到了许多工人和工程师，他们中的大多数是移民工人。所以选C。