Which of the following conditions must be true for a trust to be a simple trust?

I. The trust distributes all of its income to delegated beneficiaries every five years.
II. The trust distributes all of its trust corpus (principal) every five years.
III. The trust has 10 or fewer beneficiaries.
IV. The trust has no beneficiaries that are qualifying charitable organizations.

a. All of the above
b. III only
c. IV only
d. None of the above