The correct options are
A In the ashvamedha, a horse was let loose to wander freely.
D The raja who organised the ashvamedha was recognised as powerful.
The ashvamedha also known as horse sacrifice was a ritual perfomed by rajas. In this ritual, a horse was let loose to wander freely. If the horse wandered into another kingdom and if it was stopped, the rajas of boht the kingdoms had a fight. If the horse was allowed to pass, the raja accepted that the raja who organised the sacrifice was stronger. The raja was then recognised as very powerful and everyone brought gifts to him.