Area of three shapes

This task is about working out the area of shapes on a grid.
 
a) 
What is the area of this shape
(A) 12 cm2
(B) 13 cm2
(C) 14 cm2
(D) 15 cm2
(E) None of these. The answer is __________ cm2
 
 
 
b)
What is the area of this shape?
(A) 9 cm2
(B) 10 cm2
(C) 11 cm2
(D) 12 cm2
(E) None of these. The answer is __________ cm2
 
 
 
c)
What is the area of this shape?
(A) 5 cm2
(B) 6 cm2
(C) 7 cm2
(D) 8 cm2
(E) None of these. The answer is __________ cm2