A cell 'A' with D.P.D. = 8 is surrounded by three cells 'B', 'C' and 'D' with D.P.D. respectively 4, 6 and 5. What shall be the direction of water movement :

Question

(a)
(b) $A \to B \to C \to D$
(c) $D \to C \to B \gets A$
(d)$A \to B \gets C \to D$