Answer: C : They will need to subtract a partial year of depreciation from the book value of the second truck but not the first truck.
Explanation:
When disposing of fixed assets such as vehicles, depreciation has to be charged on them to see their Net Book Value.
Companies usually depreciate their vehicles on a yearly basis in accordance with the end of their fiscal year. This company therefore most likely depreciates on December 31.
The first truck is sold 2 days after this Depreciation so there is no need to add more depreciation to it.
However the second truck on the other hand was sold 6 months later. Depreciation needs to charged on this substantial period but since it was not for the full year, a partial one needs to be charged.