The Psychology student extended her study to determine whether there is a difference in stress levels among A students, B students, C students, and D students. She utilised the same instrument to measure stress. The stress scores of samples of students from the four universities were:

A: 68, 66, 78, 65, 62

B: 73, 65, 66, 74, 83

C: 61, 82, 79, 68, 76

D: 86, 63, 71, 74, 66

Conduct an appropriate hypothesis test, at the 5% significant level. and interpret whether there is a difference in the mean stress scores among the four universities.