Consider a Set of Electrons with an Initial Spin State $$|\psi\rangle=\left[\begin{array}{c}\sqrt{1 / 2} \\\sqrt{1 / 2}\end{array}\right]$$

Multiple Choice

Consider a set of electrons with an initial spin state
$$|\psi\rangle=\left[\begin{array}{c}\sqrt{1 / 2} \\\sqrt{1 / 2}\end{array}\right]$$
If we send these electrons into an SGx device, what is the probability that a given electron will be determined to have its spin anti aligned with the $+x$ direction?

A) 0
B) $1 / 4$
C) $1 / 2$
D) $\sqrt{1 / 2}$
E) 1