Answer:
Option C
201 feet²
Explanation:
Given in the question,
diameter of the circular graph = 16 feet
Formula to calculate the area of garden 
Area = π r²
where π is constant = 3.14
 r is the radius 
To find the radius 
 diameter/2 
16/2
8 feet
Plug in values to calculate area
 (3.14) 8²
200.96 feet²
Area of the circular garden having 16 feet diameter is 201 (approximate)