The exam lacks the power to determine which students has studied and the students who have not studied
Step-by-step explanation:
In his introductory class the professor in the motive of encouraging the students and to make them more involved in learning the subject he offers A grade to all the students
In this case the professor will lose his ability to judge the student and he will consume his time in understanding and estimating the students who has the ability to learn and the student who do not have