Herbie's Horseshoe comes up with a vegetarian horseshoe sandwich and plans to introduce it in 2024. (The market just isn't ready yet for a vegetarian horseshoe.) Herbie's wants to call it the Herbie-vore and applies for a trademark on that name. Which of the following facts, if true, would be the biggest obstacle to obtaining this trademark?

Merry Ann's Diner already has a vegetarian horseshoe sandwich

Herbie-vore is a play on the word herbivore

Herbie's has no intention of using the trademark in the next 6 months

A gardening company in California also has a product called Herbie-vore; it hasn't trademarked the name, but it has been using it for 10 years