As shown in the figure AD is the altitude on BC and AD produced meets the circumcircle of `DeltaABC` at P where DP=x. Similarly EQ=y and FR=z. If a,b,c respectively denotes sides BC, CA and AB then `a/(2x)+b/(2y)+c/(2z)` has the value equal to
A. `tan A+tanB+tanC`
B. `cotA+cotB+cotC`
C. `cosA+cosB+cosC`
D. `cos ecA+cos ecB+ cos ecC`