Select the most appropriate option that can substitute the highlighted segment in the given sentence.
Mother ordered John to switch on the light as it was time to sleep.

Correct option is C

The most appropriate option that can substitute the highlighted segment in the given sentence is: option (c) to switch off the light.
 The sentence indicates that Mother ordered John to turn on the light as it was time to sleep.
 "Switch off the light" is the opposite action, which means to turn off the light.