Ms. Ryan asked each student in her class if they have any pets. Her results are shown below. 4 students have only cats, 12 students have only dogs, 5 students have a dog and a cat, 8 students have fish, and no students have pet gerbills. Based on the information which statement is most likely true?

Ms. Ryan asked each student in her class if they have any pets. Her results are shown below. 4 students have only cats, 12 students have only dogs, 5 students have a dog and a cat, 8 students have fish, and no students have pet gerbills. Based on the information which statement is most likely true?