Which of the following situations results in a reversing difference and a deferred tax asset?

a$)$ The excess amount of a charge to the accounting records $($allowance method$)$ over a charge to

the tax return for the writedown of inventory due to obsolescence

b$)$ A trademark that is acquired directly from the government and is capitalized and amortized over

subsequent periods for accounting purposes and expensed for tax purposes

c$)$ Unrealized gains that are recognized on investments, recorded as fair value through net income

$($FV$-$NI$)$ or FV$-$OCI, and are not taxable until realized for tax purposes

d$)$ The estimated gross profit on a long$-$term construction contract that is reported in the income

statement, with some of the gross profit being deferred for tax purposes