Which of the following is not classified as an indirect tax?

Indirect taxes are levied on goods and services rather than directly on income or profits. They are typically collected by an intermediary (like a retailer) from the consumer and then remitted to the government.

Capital gains tax is a tax on the profit from the sale of an asset, such as stocks or real estate, which is considered a direct tax. This tax is levied directly on the income obtained from capital gains and is paid by the individual who realizes the gain. In contrast, the other types of taxes listed, like regressive, proportional, and progressive taxes, pertain more to how income taxes are structured rather than being classified as indirect taxes.

Regressive, proportional, and progressive taxes relate to how taxpayers are categorized based on their income levels, but they do not specifically define the mechanism of taxation being direct or indirect. Therefore, capital gains tax stands out as not being classified as an indirect tax due to its direct nature regarding income from asset sales.