A.who
The clerk will wait on whoever is next.
Yes, a clerk should take each person in order. Take the first person and then after you have finished with them take the next in line.
The clerk will wait on whom is next is the proper sentence. Who is only used when it is the subject of a verb.
I just got off the phone with the county clerk and so long as the divorce is final you can get married that day!
An admissions clerk checks all verifications needed for applicant to advance to the next level of entry.
A clerk is a person that helps file things or they can help you find what you need in a store
They would be called a clerk or customer service clerk.
No, a sales person. A clerk is someone who, quote, "works at a bank or an office," dictionary.com
the person who sell the items
Both "whom" and "whomever" work, depending on whether you want a specific person or any person at all. A good trick is to ask if you would use "he" or "him" in its place. "Who" goes with "he," and "whom" goes with "him." You can remember that by associating the words that have an "m" at the end together. (If you are talking about a woman or a girl, you should still use this trick, as "her" does not end with an "m," making it a bit harder to remember which goes with which.)
You are referring to Clerk, so a better rhyme would be Perk, though some people do pronounce Clerk to rhyme with Park.
* Clerk * Representative * Associate