Explanation:

- Gross National Product (GNP) measures the total economic output of a country, including all goods and services produced by its nationals, both domestically and abroad.

- Item 1: Consumer goods and services

- These are part of GNP as they contribute to the country's total economic output.

- Item 2: Gross private domestic investment

- This includes all private sector investment within the nation, contributing to GNP.

- Item 3: Goods and services produced by the Government

- These are included in GNP as part of the total production.

- Item 4: Net income from abroad

- This is crucial for GNP, which includes incomes earned by nationals overseas.

The correct option is Option 4: 1, 2, 3 and 4, as all these items are included in the calculation of GNP.