I'm fairly new to Facebook advertising and want to find out firstly what demographics and secondly what creative has the highest conversion for my FB Messenger bot. So far I've created 3 ad sets with the only variation in demographics being the age range; they each have the same creative displayed. Should I just rely on the CPC reported from the Facebook ads manager, or is there something else I can do akin to the Facebook Pixel that websites can use (but which presumably bots cannot)