Herb has $20,000 in an interest-bearing time deposit with the Applebottom Bank and Trust Company. While earning a relatively attractive rate of interest, Herb had to agree to not withdraw any of the funds until the end of a three-year period. Herb's investment represents a(n):A. Passbook savings account.B. Negotiable order of withdrawal (NOW) account.C. Individual deferred earnings account (IDEA).D. Certificate of deposit (CD).