Answer:
add a rebuttal to discredit the counterclaim and support his claim.
Step-by-step explanation:
The best way that Dimit can fully develop the claim in his essay that social networking improves society is by adding a rebuttal to the counterclaim that social media is distracting and leads to lower grade among students.
He can make a rebuttal by showing that social networking can be used to solve home work and encourage peer to peer discussion.