You Have Conducted an Ames Test on a Given Compound

You have conducted an Ames test on a given compound. Which of the following would be classified as a positive result on the Ames test?

A) his ^- strain grows on an his ^- plate.
B) his ^- strain grows on an his⁺ plate.
C) his⁺ strain grows on an his ^- plate.
D) his⁺ strain grows on an his⁺ plate.
E) his⁺ strain grows on either an his ^- or an his⁺ plate.