21-22A

You should mark the section "individual under 14.630". Which states in part:

(a) Any person may be authorized to prepare, present, and prosecute one
claim. A proper power of attorney, and a statement signed by the person and
the claimant that no compensation will be charged or paid for the services,
shall be filed with the office where the claim is presented. A signed writing,
which may be in letter form, identifying the claimant and the type of benefit
or relief sought, specifically authorizing a named individual to act as
the claimant’s representative, and further authorizing direct access to
records pertinent to the claim, will be accepted as a power of attorney.

An 'agent' is someone who is recognized by the VA to present claims but they
are not a Veterans Service Officer or attorney. They are accredited by the
VA.