To make television a teaching tool with beneficial results, what must be done?

A) Children must be encouraged to watch more TV than they do now
B) A government campaign must be started to ensure a TV in every home
C) Adults must monitor time spent watching and appropriateness of programs
D) Children must be exposed to more adult programs

Monitoring time spent watching and appropriateness of programs is crucial to ensure that television is used as a teaching tool with beneficial results. This allows for the selection of age-appropriate and educational programming, while also limiting excessive screen time. Encouraging children to watch more TV, ensuring a TV in every home, or exposing children to adult programs do not necessarily lead to beneficial results in using television as a teaching tool.