Which of the following claims on crowding out is correct?

Which of the following claims on crowding out is correct?

1. Crowding out is a form of quantitative easing.

2. Crowding out can happen where the public sector borrows a lot of liquidity from the financial markets.

3. Crowding out occurs where short term interest rates are higher than long term interest rates.

4. Crowding out is an expansionary monetary policy.