Rekha drew a circle of radius $2\;\text{cm}$ on a graph paper of grid $1\;\text{cm}\times1\;\text{cm}$. She then calculated the area of the circle by adding up only the number of full unit-squares that fell within the perimeter of the circle. If the value that Rekha obtained was $d\;\text{sq cm}$. less than the correct value,
In the above question what is the minimum possible value of $d?$
- $4.56$
- $5.56$
- $6.56$
- $3.56$