The correct option is A 10000200001
Squares of numbers with this form follow a pattern.
Count the number of zeros between the ones at the two ends.
In the above case there are 4 zeroes in between the ones.
∴ The square of 100001 is:
1 followed by four zeros then 2 and again four zeros, 1 at the units place.
i.e 10000200001