(C) IS THE CORRECT ANSWER
1st sector start at <0,0,0> (in the question they are calling the 1st sector as the 0th sector)
so, if we are asked to calculate the address of the 1039th sector and if we go by our assumption then they must be asking about the address of the 1040th sector.
Now, we have to calculate the <c,h,s> i.e. the cylinder number, the surface number and the sector number.
First, let's calculate the cylinder number:
we know that a cylinder will contain= 10x2x63 sectors = 1260 sectors and we need the address of the 1040th sector so it is clear that the 1040th sector is inside the 1st cylinder only, and in the question, they are representing the address of the 1st cylinder as 0 so c = 0.
Second, lets calculate the surface number:
a surface will contain = 63 sectors (NOTE: if h starts from 0 then for any number h it means that we have to cross that many surfaces in order to get to the surface we want) h = 1040/63 = 16.507 (it means that we have to cross 16 surfaces) so, h = 16.
now calculate the remaining sectors = 0.507 x 63 = 31.941 (it means that we have to cross 31 sectors) so, s=31.
hence, <c,h,s> = <0,16,31>