The Green Revolution led to an increase in the agricultural output primarily due to the use of HYV seeds. Here, HYV refers to:

The correct answer is High Yielding Variety.

Explanation:

The term HYV stands for High Yielding Variety. During the Green Revolution, which began in the mid-20th century, agricultural practices were transformed by introducing high-yielding varieties of cereal crops (specifically wheat and rice), improved irrigation systems, synthetic fertilizers, and pesticides.

These specialized seed varieties were genetically modified or selectively bred to produce significantly higher crop yields per unit of land compared to traditional seed varieties, thereby dramatically increasing overall agricultural productivity.