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

The answer to your question would be that the relative clause in the sentence is introduced by the word "who". This is a restrictive or defining relative clause in the sense that the information it provides is considered essential to the meaning of the sentence. If the information in the relative clause was dropped, the meaning of the sentence would be altered.  This relative clause identifies who the person is. Take a:

a) ? Miguel is the person

go

explanation:

because it can't be a slow, i would say possibly whoa, but there's nothing too surprising about orange juice, and because it tastes awesome it's a go drink, not food.