Their demand is the good use we ________ our spare time for our study of science and technology．

1. A.
   make from
2. B.
   make of
3. C.
   make out
4. D.
   make into

Their demand is the good use we _____ our spare time for our study of science and technology.

A．make from            B．make of          C．make out         D．make into