The correct option is C 1
Given that x, y, z are the pth,qth and rth terms of an A.P.
∴x=A+(p−1)D
y=A+(q−1)D
z=A+(r−1)D
⇒x−y=(p−q)D
y−z=(q−r)D
z−x=(r−p)D
where A is the first term and D is the common difference.
Also, x, y, z are the pth,qth and rth terms of a G.P.
∴x=aRp−1, y=aRq−1, z=aRr−1
∴xy−zyz−xzx−y=(aRp−1)y−z(aRq−1)z−x(aRr−1)x−y =(aR)∘=1