Answer A).

130.50.0.0 .Last 16 bit can be written in binary as 00000000 00000000.

Now,we need first host of first subnet So, 00000100 00000001 which will be 130.50.4.1

First host of 4th subnet will be 00010000 00000001 which will be 130.50.16.1

130.50.0.0 .Last 16 bit can be written in binary as 00000000 00000000.

Now,we need first host of first subnet So, 00000100 00000001 which will be 130.50.4.1

First host of 4th subnet will be 00010000 00000001 which will be 130.50.16.1