Which set has the greatest range?

a
{10, 14, 8, 19, 22, 13, 44}
b
{19, 16, 50, 18, 29, 23, 37}
c
{11, 9, 31, 29, 15, 17, 20, 24}
d
{12, 6, 24, 20, 44, 15, 29}