In 2020, Luigi earned $9,000 in net investment income and incurred $14,000 of investment interest expense. Luigi paid off the loan in early 2021, so he only paid $2,000 of investment interest expense in 2021. He earned $10,000 of net investment income in 2021. How much investment interest expense can Luigi deduct in 2021?

A) $10,000

B) $7,000

C) $2,000

D) $0