$$0.05$$ M $$CuSO_4$$ when treated with $$0.01$$ M $$K_2Cr_2O_7$$ gives green colour solution of $$Cu_2Cr_2O_7$$. 

The two solutions are separated as shown below : [SPM : Semi Permeable Membrane]. Due to osmosis :

A

Molarity of $$CuSO_4$$ solution is lowered.

B

Molarity of $$K_2Cr_2O_7$$ solution is lowered.

C

Green colour formation observed on side Y.

D

Green colour formation observed on side X.