$3)$ Cairo Corporation purchased the following debt securities during $2021$ and properly classified them as $$Available for Sale$$ securities:

Security Cost Fair Value $12/31/2021$

A $$40,000$ $$49,000$

B $$70,000$ $$66,000$

C $$28,000$ $$39,000$

Cairo did not own any other securities$.$ How much of an unrealized gain$/($loss$)$ will be reported by Cairo Corporation in the December $31,2021$ income statement related to the investments?

a$)$ $ $16,000.$ b$)$ $ $20,000.$

c$)$ $ $0.$ d$)$ d$)(4,000).$