a line makes angles alpha, beta,gamma with x axis, y-axis and z-axis.
if direction cosines are +-(1/root3),
+-(1/root3),+-(1/root3), then
alpha = beta = gamma
Or
alpha + beta + gamma = 3
Or
alpha + beta + gamma = 0
Or
alpha + beta = gamma
if cosθ = 1/√3, then all the angles are either θ or π-θ
sure looks like A to me.