question_answer

If the plane \[2ax-3ay+4az+6=0\] passes through the mid-point of the line joining the centres of the spheres \[~{{x}^{2}}+{{y}^{2}}+{{z}^{2}}-8y+6x-2z=13\] and \[~{{x}^{2}}+{{y}^{2}}+{{z}^{2}}-10x+4y-2z=8,\] then a equals to

A)  1                                

B)  \[-1\]

C)  \[-2\]   

D)  2

E)  None of these