Almost a Librarian

My last class started this week!

I take the certification test this weekend.  I took the practice test online and got them all right but this one:

4. A library media center uses parent volunteers
to perform a variety of tasks relating to the
school library program. Which of the following
considerations is most likely to ensure an
effective result from a parent volunteer
program?

(A) Volunteers are expected to be present on
specified days of the week at specified
times.
(B) Volunteers are assigned staff members
to work with who supervise their
activities and provide direction.
(C) Volunteers are permitted to take work
off-site in order to complete it.
(D) Volunteers have prior experience working
in a library-related field.
(E) Volunteers are given the freedom to
select or reject duties at their discretion.

Here's a hint-you have to remember not to answer like a normal human, but like a librarian (very concerned with detail and getting things exactly right).