Black, Inc. is an ESOP-owned company with three employees: Kermit, age 62, who has participated in the plan for 21 years; Isaac, age 38, who has participated in the plan for eight years; and Nathan, age 28, who has participated in the plan for seven years. Which of the following correctly describe Black, Inc.'s obligation to permit any of its employees to diversify his account?
A. Black, Inc. is not required to permit any of its employees to diversify his account
B. Black, Inc. must permit all three employees to diversify their accounts, because all three are vested
C. Black, Inc. must permit Isaac and Kermit to diversify their accounts because they have both participated in the plan for over 10 years
D. Black, Inc. must permit only Kermit to diversify his account because he has participated in the plan for over 10 years and is over age 55