Answer:
Option A is correct.
Step-by-step explanation:
Given:
AG = 6 ft ⇒ Radius of the circle , r = 6 ft
⇒ GB = AG = 6 ft
To find: Area of shaded Segment.
Area of Shaded Segment = Area of Sector AGBA - Area of Δ AGB
Sector AGBA forming 90° angle at center. 
Area of Sector = 
Area of Sector AGBA = 
= 
= 
ΔAGB is a right angled triangle.
So, Area of ΔAGB = 
= 
= 
= 
Area of Shaded Segment = 28.26 - 18 = 10.26 ≈ 10.3 ft²
Therefore, Option A is correct.