(A)
Since it is a mirror and both sides have μ1andμ1 refractive index.
Hence only 1 image will be formed.
(B)
There will be formation of two images as one will form right side above the axis and one will form on right side below the optical axis.
(C)
Only one image will be formed as the refractive index of the surrounding of the lens is same.
(D) For this case.
There will be three image formation in the three region 1, 2, 3 due to combination of different refractive index.