Which of the following datasets has the smallest variance?
{2,4,6,8}\{2, 4, 6, 8\}{2,4,6,8}
{4,4,6,6}\{4, 4, 6, 6\}{4,4,6,6}
{5,5,5,5}\{5, 5, 5, 5\}{5,5,5,5}
{1,5,5,9}\{1, 5, 5, 9\}{1,5,5,9}