If a circle passes through the point (a, b) and cuts the circle x² + y² = p² orthogonally, then the equation of the locus of its centre is

2ax + 2by – (a² – b² + p²) = 0

x² + y² – 3ax – 4by + (a² + b² – p²) = 0

2ax + 2by – (a² + b² + p²) = 0