800 local trains am every day between P and S in one direction. Q. R. U. V and T are different junctions. The cost (in ₹ ) of travelling on the train between different stations is given on the arrows in the figure shown. Each train takes the least expensive route between P and S.

Which route will the first 400 trains take on any given day?

A

P-V-T-S

B

P-U-T-S

C

P-U-S

D

P-Q-R-S