Nathan donated various amounts to charity. What total amount can he use to determine his deduction for charitable contributions?

To determine the total amount Nathan can use for his deduction for charitable contributions, it is important to consider the IRS guidelines on deductibility and how they relate to Nathan's total contributions. If Nathan's charitable contributions totaled $300, he can claim the full amount as a deduction, provided that the contributions were made to qualified organizations and he has proper documentation for his donations.

Under IRS rules, taxpayers can deduct cash contributions made to qualified charitable organizations. However, the total deductible amount depends on the contributions he made within a tax year and the limitations based on his adjusted gross income. If Nathan has substantiated his donations appropriately, then the total of his contributions is indeed $300.

For the options provided, this means that if Nathan has documented $300 in charitable donations, that is the total he would count toward his deduction, aligning with IRS rules and allowing him to maximize his tax benefit.