Two unknown resistance X and Y are connected to left and right gaps of a meter bridge and the balancing point is obtained at 80 cm from left. When a `10Omega` resisance is connected in parallel to `x`, balance point is 50 cm from left. The values of X and Y respectively are
A. `40Omega, 9Omega`
B. `30Omega, 7.5 Omega`
C. `20Omega, 6 Omega`
D. `10Omega, 3Omega`