Explanation:

- Option 1: Clouds absorb the radiation released from the Earth’s surface.

Clouds trap heat by absorbing some radiation. However, the main effect is reflecting this radiation back, not just absorption.

- Option 2: Clouds reflect back the Earth’s radiation.

Correct! Clouds act like a blanket, reflecting radiation back and keeping temperatures higher. This higher temperature reduces dew formation.

- Option 3: The Earth’s surface would have low temperature on cloudy nights.

This is incorrect. Cloudy nights are generally warmer because clouds keep heat from escaping.

- Option 4: Clouds deflect the blowing wind to ground level.

This isn't directly related to dew formation and wind plays a minimal role in the process.

In summary: Clouds act as insulators, keeping the ground warm and reducing dew on cloudy nights.