Which informal fallacy is committed in the following statement: Of course you want to buy XYZ toothpaste. There must be a reason why 90 percent of India brushes with XYZ toothpaste.

The pitch rests on the mere popularity of the toothpaste, not on any real merit.

It urges you to buy XYZ because ninety percent of India uses it.

The number of users says nothing about whether the toothpaste is actually good for you.

Wide acceptance is treated as if it were evidence of quality.

Appealing to the crowd in place of reasons is the fallacy of argumentum ad populum.