Form 941-X is known as:

Form 941-X is indeed known as the Adjusted Employer’s Quarterly Federal Tax Return. This form is specifically used by employers to correct errors made on previously filed Form 941, which reports income taxes, social security tax, or Medicare tax withheld from employee's paychecks, along with the employer's portion of social security and Medicare tax. The ability to adjust these filings is crucial, as it ensures that the correct tax amounts are reported and paid to the IRS, maintaining compliance with federal tax regulations.

It's important to note that this form allows for rectifications related to wage reporting discrepancies, underreporting, miscalculations, or other mistakes that may have occurred. Correcting these errors helps to avoid potential penalties and ensures that both the employer and the employees' tax records remain accurate.

The other choices refer to entirely different forms or functions within tax reporting and do not serve the purpose of correcting quarterly tax returns, which further solidifies why "Adjusted Employer's Quarterly Federal Tax Return" is the accurate designation for Form 941-X.