The correct answer is option 3: Westerlies.

The winds that blow from the subtropical high pressure belts towards the subpolar low pressure belts are known as westerlies. These winds are characterized by their westward flow, hence the name "westerlies." They are found in both the Northern Hemisphere and the Southern Hemisphere.

Option 1, easterlies, is incorrect. Easterlies are winds that blow from the east towards the west. They are found near the polar regions.

Option 2, trade winds, is also incorrect. Trade winds are the prevailing winds that blow from the high-pressure areas towards the equator. They are found in the subtropics.

Option 4, western disturbances, is not related to the wind patterns described in the question. Western disturbances refer to weather systems that move from the west to the east, affecting regions like South Asia and the Mediterranean.

Therefore, the correct answer is option 3, westerlies.