Plz answer with explanation

Figure shows a three arm tube in which a liquid is filled upto levels of height /. It is now rotated at an angular frequency about an axis passing through arm B. The angular frequency at which level of liquid in arm B becomes zero is


(a) $\sqrt{\frac{2g}{3l}}$

(b) $\sqrt{\frac{g}{l}}$

(c) $\sqrt{\frac{3g}{l}}$

(d) $\sqrt{\frac{3g}{2l}}$