Which data set has the greatest spread?

Set A – {84, 91, 87, 77, 94, 89, 74}
Set B – {89, 73, 84, 91, 87, 77, 94}
Set C – {73, 84, 89, 88, 77, 91, 87, 90}
Set D – {84, 89, 88, 82, 91, 87, 99}

A.
Set A
B.
Set B
C.
Set C
D.
Set D