Consider the following two normal curves:
Which has the larger mean and which has the larger standard deviation?
(A) Curve " $a$ " has the larger mean and the larger standard deviation.
(B) Curve " $a$ " has the larger mean, and curve " $b$ " has the larger standard deviation.
(C) Curve "b" has the larger mean, and curve " $a$ " has the larger standard deviation.
(D) Curve " $b^{\prime \prime}$ has the larger mean and the larger standard deviation.
(E) Curve "b" has the larger mean, and curves " $a$ " and "b" have the same standard deviation.