Greg sold an apartment building he owned for 20 years. He paid $100,000 for it, and made $300,000 worth of improvements. His depreciation was $2,500 per year. He sold the building for $1,000,000 and paid $60,000 in commission to the broker. What is Gregs capital gain on the apartment?

A. $450,000

B. $520,000

C. $590,000

D. $600,000