A/B testing for channel preference

Hi. Right now my organization runs a lot of promotional campaign every month. We send email, SMS and WhatsApp to all customers for each campaign. I am running a project to identity the best channel for a promotional campaign. All the channels have have similar range of CTR. But using all channels for all customers is a cost to company. The aim is to reduce the cost. Is A/B testing frequenist or Bayesian the ideal method. If no what should …

a/b testing b testing datascience testing