Which one of the following statements with regard to marketable securities is incorrect?

A. In the trading portfolio of marketable equity securities, unrealized gains and losses are recorded on the income statement.

B. In the available-for-sale portfolio of marketable equity securities, unrealized gains and losses are recorded on the income statement.

C. The held-to-maturity portfolio consists only of debt securities.

D. Securities may be transferred from the held-to-maturity to the available-for-sale portfolio.