The correct answer is option 3, Israel. Indian forces have acquired Heron drones from Israel to enhance their surveillance capabilities.

Option 1, USA, is not the correct answer because the Heron drones are not acquired from the United States.

Option 2, Russia, is not the correct answer because the Heron drones are not acquired from Russia.

Option 4, Japan, is not the correct answer because the Heron drones are not acquired from Japan.

The Heron drones are unmanned aerial vehicles (UAVs) developed by Israel Aerospace Industries (IAI). These drones are known for their long endurance, large payload capacity, and advanced surveillance capabilities. They are used by various countries around the world, including India, for intelligence gathering, reconnaissance, and surveillance purposes.

In summary, the Indian forces have acquired Heron drones from Israel to enhance their surveillance capabilities.