Explanation:

- Capital: Represents accumulated wealth or resources. It's a stock, not a flow, as it's measured at a specific point in time.

- Income: Money earned over a period of time. It is a flow because it's measured per unit of time, like monthly or yearly.

- Investment: Refers to money spent towards earning returns, often over time. As it occurs over time, it's considered a flow.

- Depreciation: Describes the reduction in value of an asset over time. It's a flow since it is calculated regularly, such as yearly.

The correct answer is Option:1, Capital .

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