Which of the following advertisements is likely not based on proven facts?

The FDA has approved the latest flea and tick medication for all ages of dogs.
An independent research company found only around 10% of consumers had side effects.
Three out of four consumers prefer Grandma’s Cookies than any other competitor.
The secret ingredient in the headache medicine cures all types of headaches.

Three out of four consumers prefer Grandma’s Cookies than any other competitor. This statement is likely not based on proven facts as it is subjective and not supported by research or data.