Which word begins the relative clause in this sentence?

Miguel is the person who is right for this job.

A. who

B. this

C. person

D. job

I think the correct answer from the choices listed above is option A. It is "who" that signifies the relative cause in the sentence. Relative clauses are clauses starting with the relative pronouns who*, that, which, whose, where, when. They are most often used to define or identify the noun that precedes them.