Choose the correctly punctuated sentence.

a. In one-on-one interviews, which are the most common type, you will sit down with a company representative to discuss the position and your qualifications.
b. In one-on-one interviews, which are the most common type you will sit down with a company representative to discuss the position and your qualifications.
c. In one-on-one interviews which are the most common type you will sit down with a company representative to discuss the position and your qualifications.