Which statement is true?

Consider the following scenario:
In a multiform application, the user started in FormA.
1. From FormA, the user invoked FormB using CALL_FORM.
2. From FormB, the user invoked FormC using OPEN_FORM.
3. From FormC, the user invoked FormD using OPEN_FORM.
4. From FormB, the user invoked FormE using CALL_FORM.
There is an additional form in the application, called FormF.
Which statement is true?

A.
FormF can be invoked from FormC using CALL_FORM.

B.
FormF can be invoked from FormA using OPEN_FORM.

C.
FormF can be invoked from FormD using CALL_FORM.

D.
FormF can be invoked from FormE using CALL_FORM.

E.
FormF can be invoked from FormB using OPEN_FORM.