What is the characteristic function of a standard normal distribution X∼N(0,1)X \sim N(0, 1)X∼N(0,1)?
et2/2e^{t^2/2}et2/2
e−t2/2e^{-t^2/2}e−t2/2
eite^{it}eit
e−t2e^{-t^2}e−t2