In the third Battle of Panipat Marathas were defeated by :

The correct answer is (b).

The Third Battle of Panipat was fought on 14 January 1761, near Panipat, about 97 km (60 mi) north of Delhi, in the present-day state of Haryana, India. The battle was fought between the Maratha Empire and the invading Afghan army of Ahmad Shah Durrani. The Marathas were led by Sadashivrao Bhau, while the Afghans were led by Ahmad Shah Durrani.

The battle was a decisive victory for the Afghans, who routed the Maratha army. The Maratha leader, Sadashivrao Bhau, was killed in the battle. The defeat at Panipat marked the beginning of the decline of the Maratha Empire.

The Mughals were a Muslim dynasty that ruled over most of India from the 16th to the 18th centuries. The Mughal Empire was founded by Babur, a descendant of Timur and Genghis Khan. The Mughals were a powerful and sophisticated empire, and they made significant contributions to Indian art, architecture, and culture.

The British East India Company was a British trading company that was founded in 1600. The company was granted a monopoly on trade with India by the British Crown. The British East India Company gradually became more powerful in India, and it eventually took control of much of the subcontinent.

The Rohillas were a Pashtun tribe that lived in the Rohilkhand region of northern India. The Rohillas were a powerful and independent tribe, and they often clashed with the Mughal Empire. In 1774, the Rohillas were defeated by the British East India Company.

The Marathas were a Hindu warrior group that emerged in the 17th century. The Marathas were a powerful and expansionist force, and they eventually controlled much of central and western India. The Maratha Empire was founded by Shivaji Maharaj in 1674. The Maratha Empire reached its peak under the leadership of Bajirao I (1720-1740).

The Third Battle of Panipat was a major turning point in Indian history. The defeat of the Marathas at Panipat marked the beginning of the decline of the Maratha Empire. The battle also opened the door for the British East India Company to expand its power in India.