Correct option is A
✅ (a) Depreciation the tractor to zero at the end of its useful life: • In the straight-line depreciation method, the asset’s cost is reduced equally every year until it reaches zero or salvage value at the end of its useful life. • Formula: (Cost – Salvage Value) / Useful life = Annual depreciation • This method provides a simple and consistent accounting value.
❌ (b), (c), (d): • These describe declining balance or variable depreciation methods, not straight-line.