(D) 0.8
The total number of people in sample study, n(S) = 642.
The number of people who have high school certificate, n(E) = 514.
So, the probability that the person selected has a high school certificate
= n(E)/n(S)
= 514/642
= 0.8
Hence, the probability that the person has a high school certificate is 0.8.