Explanation:

- Depreciation:

- Correctly known as the consumption of fixed capital.

- Represents the wear and tear or obsolescence of physical assets over time.

- Helps in allocating the cost of an asset over its useful life.

- Option: 1 -

- Net Investment:

- Equals total investment minus depreciation.

- Measures the actual addition to the stock of capital.

- Appreciation:

- Opposite of depreciation.

- Increase in the value of an asset over time.

- Gross Investment:

- Total amount spent on new capital before adjusting for depreciation.

- Does not account for the consumption of fixed capital.