In January 2021, a taxpayer takes out a $500,000 mortgage to purchase a main home. The loan is secured by the main home. In Feb. 2021, the taxpayer takes out a $250,000 loan to purchase a vacation home. The loan is secured by the vacation home. The equity in the main home increased and the taxpayer takes out a $50,000 second mortgage. The taxpayer used the money to improve the vacation home. Which of the following is correct? A. The interest for the first mortgage on the main home and the vacation home are deductible. B. All of the mortgage interest is deductible C. Only interest (first and second) on the taxpayer's main residence is deductible. D. The interest on the vacation home is only deductible if it secured by the main residence.