Which of the following is NOT an itemized deduction?

Capital losses are not classified as an itemized deduction. Instead, they are utilized to offset capital gains when calculating taxable income. If capital losses exceed capital gains, taxpayers can use those losses to offset a limited amount of ordinary income and carry any excess forward to future tax years. This treatment differs from the other options, which are specifically itemized deductions that reduce the taxpayer's taxable income when they choose to itemize their deductions on their tax return.

Mortgage interest, charitable donations, and medical expenses are all recognized as itemized deductions. Taxpayers can choose to itemize these deductions instead of taking the standard deduction to potentially lower their taxable income significantly. Each of these deductions has specific rules and limitations that apply, but they all fit within the framework of itemized deductions designed to provide tax benefits for certain expenses incurred during the year.