The decline of the Mauryan Empire led to the rise of smaller kingdoms and invasions in Punjab by:

Indo-Greeks
Scythians (Sakas)
Parthians (Pahlavas)
All of the above

The correct answer is: d) All of the above

The Mauryan Empire was a great Indian empire that ruled over most of the Indian subcontinent from the 4th to the 2nd century BCE. It was founded by Chandragupta Maurya, who united the Indian subcontinent under one rule for the first time. The Mauryan Empire reached its peak under the reign of Ashoka the Great, who is known for his Buddhist reforms and his promotion of non-violence.

The Mauryan Empire began to decline in the 2nd century BCE. This was due to a number of factors, including internal political instability, economic problems, and foreign invasions. The empire finally collapsed in 185 BCE.

After the collapse of the Mauryan Empire, the Indian subcontinent was divided into a number of smaller kingdoms. These kingdoms were often at war with each other. In addition, the Indian subcontinent was invaded by a number of foreign powers, including the Indo-Greeks, the Scythians (Sakas), and the Parthians (Pahlavas).

The Indo-Greeks were a group of Greeks who invaded the Indian subcontinent in the 2nd century BCE. They established a number of kingdoms in the northwestern part of the subcontinent. The Scythians (Sakas) were a group of nomadic people from Central Asia who invaded the Indian subcontinent in the 2nd century BCE. They established a number of kingdoms in the northwestern part of the subcontinent. The Parthians (Pahlavas) were a group of nomadic people from Central Asia who invaded the Indian subcontinent in the 2nd century BCE. They established a number of kingdoms in the northwestern part of the subcontinent.

The invasions of the Indo-Greeks, the Scythians (Sakas), and the Parthians (Pahlavas) had a significant impact on the Indian subcontinent. They led to the decline of the Mauryan Empire and the rise of a number of smaller kingdoms. In addition, they introduced new cultures and ideas to the subcontinent.