Explanation:

Here’s what each option actually means:

- Money income

This is the national income measured at current market prices. It doesn't adjust for inflation or purchasing power. When you see "calculation of National Income at Market Prices," it really means we’re talking about money income.

- Real income

Now, real income adjusts for inflation—it’s national income measured at constant prices. It tells you about actual purchasing power, not just what’s on paper.

- Non-monetary income

This one is about goods and services that people get without using money—think home-grown vegetables or housework. Not included in official market price calculations.

- None of these

Well, in this case, one of the above options does actually fit.

Correct Answer: Option 1 - Money income