After the physics final exam, the study committee asked the teacher about his grades and asked, "Teacher, this physics test was not difficult. I think all the students in our class will pass. " The teacher said, "Your previous sentence was right. The latter sentence is incorrect. ". Can it be inferred from this text? ['It was difficult to take the physics test.', 'The class passed.', 'Although physics is not difficult this time, there are still classmates who failed.', 'Although the physics test is difficult, the class has passed.']