Given the histogram, where the x-axis represents the number of years employees worked for the Department of Defense and the y-axis represents the frequencies. What percentage of those surveyed worked longer then 30 years? (Note the lower and upper limit for the first class is 0, 9 respectively.)

A. 17%

B. 24%

C. 28%

D. 87%

E. None of the above are correct.

30 20 10 0 20 10 37 20 30 30 17 40 10 50 1 60