The following is paramagnetic

(A) In CaCl₂, Electronic configuration of Ca⁺²: [Ar] ; zero unpaired electrons, diamagnetic.

(B) In CuCl₂, Electronic configuration of Cu⁺²: [Ar]3d⁹ ; one unpaired electron, para magnetic.

(C) In ZnCl₂, Electronic configuration of  Zn⁺²: [Ar]3d¹⁰ ; zero unpaired electrons, diamagnetic.

(D) In NaCl, Electronic configuration of Na⁺: [Ne] ; zero unpaired electrons, diamagnetic.