The answer to this problem is 'B'.
This is because to find the area of a circle your formula is
A = 3.14•r²
So your first step is
1. Find the radius by dividing the diameter (6) by 2
6/2 = 3 Radius= 3
Now that you have found the radius (3) plug the number in the formula
2. A = 3.14•3²
OR
A = 3.14•3•3
Finally, solve the last step - Find the area
3.14 • 3 • 3 = 28.26
A = 28.26