A deductible temporary difference is a difference between the carrying amount of an asset or liability for tax purposes that is less than its carrying amount for accounting purposes, which will result in a reduction of future taxable income when the difference reverses. Based on this definition:

B. Vehicle revalued for tax purposes but not for accounting purposes, with tax base lower than its carrying value by 250, represents a deductible temporary difference. When the vehicle is sold or disposed of, the tax base will be higher than the amount that will be deductible for tax purposes, resulting in a lower tax liability.

A. Research expenditure that was accrued in the amount of 50, but will be tax deductible on a cash basis, also represents a deductible temporary difference, as the expense will reduce taxable income in the future when paid.

C. Accounts receivable with a carrying amount of 80 when their collection will have no tax consequences does not represent a temporary difference, as there's no difference between the tax basis and the accounting carrying amount.

Therefore, both choice A and B represent deductible temporary differences.