He who has suffered the most in the cause should speak.( Begin with: Let him...)​

let him decide what he wants to do??

should be allowed to speak, is the correct replacement of the bold part. In the sentence, both clauses are connected by the subject "he", i.e. auxiliary verb 'has' and modal 'should'. The doer/subject of both is 'he' only.

Hence, 'should be allowed to speak' is the right choice.

Hope that helps!

it’s important not to respond to the bully because doing so generally just escalates the problem.

tell a trusted adult about what is happening and save the evidence. you should also let your internet or cell phone provider know, along with the operator of the site if it is happening online.

if the bullying continues, notify the local police and consider consulting an attorney if it becomes serious.

school authorities may also become involved if it involves students on campus.