What is the mechanism at work that causes the increase in a country's government spending to have an impact on foreign countries' production and income?

What will be an ideal response?

POSSIBLE RESPONSE: When government spending increases, gross domestic product (GDP) rises directly as government spending constitutes part of the aggregate demand for the country's production, as shown in Y (GDP) = AD (Aggregate Demand) = C + Id + G + X - M. Here, C = Domestic consumption, Id = Investment, G = Government expenditure, X = Exports, and M = Imports. Furthermore, the spending multiplier takes over, so the increase in GDP and income can be more than the increase in government spending. Imports rise together with the increase in GDP and income because imports are a positive function of GDP, i.e., M = M(Y). This country's imports are foreign exports. The increase in foreign exports increases aggregate demand for foreign production, so foreign production and income increase.