The correct option is B Rajasuya
Rajasuya Vedic sacrifies was a royal conservation ceremony. It was a yajna or sacrifice performed by the ancient kings of India who considered themselves powerful enough to be an emperor. Rajasuya, like the ashwamedha would occur after the return of generals of the king from a successful military campaign.After conquering the kings of other kingdoms and collecting tribute from them, the general would invite the vanquished kings to attend the sacrifice ceremony. All the vanquished kings would in effect consider the performer of these sacrifices as an emperor.In case of rajasuya there is no horse involved. The generals plan their route themselves.