What is the number of nearest neighbours for a given lattice point in CCP lattice?

12

The correct answer is option 2. 12.

Cubical closed packing structure (CCP)

Fourth layer will overlap with 1st layer, and it is also labelled as ABC-ABC.... type packing.

This type of close packing is highly efficient and 74% space in the crystal is filled. Each sphere is in contact with twelve spheres. Thus, the coordination number is 12 of this structure.