Concept:Different extension methods rely on different skills. Only methods based on reading require farmers to be literate.
Explanation:Radio is an audio medium. Farmers only need to listen, so both literate and illiterate farmers can benefit.
Television uses sound and visuals. Farmers only need to watch and listen, so literacy is not required.
Demonstration is a practical, hands-on method. Farmers learn by observing and doing, so it works for all farmers.
Newspapers present information through written text. A farmer must read and understand the content to benefit from it.
Therefore, among the given options, newspapers can benefit only literate farmers.
Answer:D. newspapers