since stocks can be traded online, which purpose is best served by markets? markets regulate transactions…

Brief Explanations:

Markets are physical or virtual platforms where buyers and sellers come together to trade. They are the location where trades actually take place. Regulations are often set by external entities like government bodies, assets are owned by investors and not sold by the market in the sense described here, and while security is an aspect, the core function is the venue for trade.

Answer:

Markets are where the trades actually occur