Which of the following statements regarding depreciation is true?

a$.$ Regardless of the depreciation method, the amount of total depreciation expense during the life of the asset will be the same.

b$.$ If using the straight$-$line method, the amount of depreciation expense during the first year is higher than that of the double$-$declining$-$balance method.

c$.$ If using the units$-$of$-$activity method, it is possible to depreciate more than the depreciable cost.

d$.$ If using the double$-$declining$-$balance method, the total amount of depreciation expense during the life of the asset will be the highest.