Is that post #sponsored?

Have you ever seen a TV commercial with a celebrity or star athlete talking about how great a product is? You probably realized that they were paid for their endorsement, and it still may have influenced you to buy the product.

What if you saw that same celebrity post on social media about a particular sports drink, with the hashtag #recoverfaster? Would you think it was a paid promotion? It can be hard to tell.

Source: FTC Scam Alert Feed
Is that post #sponsored?