Which of the following is not a category into which Ashoka’s monuments may be grouped?

The correct answer is D. Caves.

Ashoka’s monuments can be grouped into three categories: stupas, pillars, and edicts. Stupas are dome-shaped structures that were used to house relics of the Buddha. Pillars are tall, stone columns that were used to commemorate Ashoka’s deeds and spread his message of peace. Edicts are stone inscriptions that were carved into rocks and pillars. They contain Ashoka’s teachings on Buddhism and his policies for the Mauryan Empire.

Caves are not a category into which Ashoka’s monuments may be grouped. However, there are many Buddhist caves in India that were built during Ashoka’s reign. These caves were used as monasteries and temples.