For tax years ending after 2017, which of the following statements is incorrect with respect to the treatment of a net operating loss by a calendar year C corporation?

1. The deduction for any carryover year of the NOL is limited to 80% of taxable income (determined without regard to the NOL deduction).

2. A corporation may claim a dividends received deduction in computing an NOL.

3. An NOL is generally carried back 2 years and forward 20 years.

4. Unlike individuals, corporations do not adjust their NOLs for net capital losses or nonbusiness deductions.

5. None of these.