Let X be a normal random variable with mean 1 and variance 4. The probability P{X < 0} is A. 0.5 B. greater than zero and less than 0.5 C. greater than 0.5 and less than 1.0 D. 1.0

The correct answer is $\boxed{\text{B}}$.

A normal random variable with mean 1 and variance 4 has a standard deviation of 2. The probability that a normal random variable is less than 0 is equal to the area under the curve to the left of $x=-2$. This area is less than 0.5 but greater than 0.

The following figure shows the probability density function of a normal random variable with mean 1 and variance 4. The shaded area is the area under the curve to the left of $x=-2$.

[asy]
unitsize(1 cm);

draw((0,-3)–(0,3));
draw((-3,0)–(3,0));

real g(real x) {
return exp(-(x-1)^2/4)/sqrt(2*pi);
}

draw(graph(g,-3,3),red);

label(“$x$”, (3,0), E);
label(“$y$”, (0,3), N);
label(“$f(x)$”, (1.5,0.15), S);
label(“$P(X<0)$”, (-2,0.15), S);
[/asy]