Which of the following is NOT considered a type of business tax?

Sales tax is generally imposed on the sale of goods and services, making it a transaction-based tax. While businesses collect sales tax from consumers at the point of sale, it does not directly tax the business's income or profits but rather the sale itself. This differentiates it from the other types of taxes listed, which are directly associated with business operations and profitability.

By contrast, self-employment tax refers to the taxes that self-employed individuals must pay, which funds Social Security and Medicare. Income tax is a tax on the net income of businesses, taking into account the profits earned during the taxable period. Employment taxes encompass various taxes withheld from an employee's paycheck, including Social Security and Medicare taxes, as well as unemployment taxes that employers pay on behalf of their employees.

This clarification helps to understand the distinction in the context of business taxation: the sales tax is more about the retail aspect of transactions rather than a direct business tax on income or payroll, which is why it stands apart from the other options presented.