在正三棱柱\((\)底面是正三角形的直三棱柱\()ABC-A _{1} B _{1} C _{1}\)中，\(AB=2\)，\(E\)，\(F\)分别为\(A _{1} C _{1}\)和\(A _{1} B _{1}\)的中点，当\(AE\)和\(BF\)所成角的余弦值为\( \dfrac {1}{4}\)时，\(AE\)与平面\(BCC _{1} B _{1}\)所成角的正弦值为\((\:\:\:\:)\)
A. \( \dfrac { \sqrt {6}}{2}\)
B. \( \dfrac { \sqrt {6}}{4}\) C. \( \dfrac { \sqrt {10}}{4}\)或\( \dfrac { \sqrt {6}}{4}\) D. \( \dfrac { \sqrt {10}}{2}\)
