Extended Fund Facility (EFF) : For structural balance of payments problems.

Here's the analysis of each pair:

• 1. Extended Fund Facility (EFF) : For structural balance of payments problems. The Extended Fund Facility (EFF) is indeed provided by the IMF to member countries facing serious medium-term balance of payments problems because of structural impediments or slow growth. This statement is correct.

• 2. Rapid Credit Facility (RCF) : Quick and concessional lending for high-income countries. The Rapid Credit Facility (RCF) provides rapid financial assistance to low-income countries (LICs) facing urgent balance of payments needs. It is concessional but not for high-income countries. This statement is incorrect.

• 3. Resilience and Sustainability Facility (RSF) : Short-term liquidity line. The Resilience and Sustainability Facility (RSF) provides affordable, long-term financing to help countries address long-term structural challenges like climate change and pandemic preparedness. It is not a short-term liquidity line. This statement is incorrect.

Only one pair (Pair 1) is correctly matched.

The correct option is (A).

A) Only one