Import cover is a critical economic indicator that measures the number of months of imports a country can afford using its foreign exchange reserves. It is calculated using the formula: Import Cover = (Total Foreign Exchange Reserves) / (Average Monthly Imports). This metric assesses a country's external stability and its ability to withstand shocks to the balance of payments or sudden stops in foreign currency inflows. While other options describe the import-to-GDP ratio (Option A), total import volume (Option B), or trade balance/terms of trade (Option C), only Option D correctly identifies the relationship between reserves and import duration.