Which of the following statements regarding Grantor-Retained Interest Trusts (GRIT) is correct?

I. Once established, a grantor-retained interest trust is irrevocable.

II. It is best to put assets that are expected to grow rapidly into this type of trust.

III. If the donor does not outlive the trust period, the value of the trust property will be included in the donor's taxable estate.

Group of answer choices

I only

II only

I, II, and III

I and II only