Suppose a Professor Counts the Final Exam as Being Equal

Multiple Choice

Suppose a professor counts the final exam as being equal to each of the other tests in her course, and she will also change the lowest test score to match the final exam score if the final exam score is higher. If a student's four test scores are 85, 83, 54, and 95, what is the lowest score the student can earn on the final exam and still obtain at least an 80 average for the course? ​

A) 69
B) 83
C) 90
D) 72
E) 84