If A(z1), B(z2) and C(z3) are three points on the argand plane where |z1 + z2| = ||z1| - |z2|| and |(1 - i)z1 + iz3| = |z1| + |z3 - z1|,
where i= √(- 1) then
(a) A, B and C lie on the fixed circle with centre (z1 + z2)/2
(b) A, B and C are collinear points
(c) ABC form an equilateral triangle
(d) ABC form an obtuse angled triangle