$15.$ Z Corp was organized as a $$C$$ corp in $2005,$ and made an $$S$$ election in $2010.$ Its sole asset is a hotel with a basis of $5,000,000$ and a fair market value of $$11,000,000$ at the time of the $$S$$ election. The hotel was sold for $$15,000,000$ in $2022$ in a taxable transaction. How much gain is taxable to the corporation?

a$.$ $$10,000,000$

b$.$ $$5,000,000$

c$.$ $$6,000,000$

d$.0$

e$.$ None of the above