mona owns a rental house that she has rented to various tenants since September 2001. The backyard fence fell into disrepair in June 2018. She had it replaced June 27, 2018 for $8399. If only Alex to use special appreciation for the new fans, what is the amount of current depreciation excluding the amount of current to special appreciation for this asset?

a. zero dollars

b. $210

c. $315

d. $420