There is no 'best' affiliate program to work in, as such a thing doesn't exist. What exists is a sweet spot, which is the best fit between your abilities and the needs of a particular program. However, not all affiliate programs are equal. Some are better than others.
So, the best affiliate program to work in is the one that best fits your skills and interests [niche], and that also provides opportunities for growth and development.
Here's related information that you may find helpful - 81 Affiliate Marketing Related FAQs and Answers to see if they may help you move forward as an Affiliate Marketer with confidence.
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