In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Ex Input:
Problem: a circle is inscribed in a triangle of side 6 cm . and a square is inscribed in the circle . what is the area of square ? 
Options: ['a ) 4 cm ^ 2', 'b ) 6 cm ^ 2', 'c ) 5 cm ^ 2', 'd ) 7 cm ^ 2', 'e ) 8 cm ^ 2']

Ex Output:
b


Ex Input:
Problem: find the circumference and area of radius 6 cm . 
Options: ['a ) 113 cm ²', 'b ) 144 cm ²', 'c ) 154 cm ²', 'd ) 184 cm ²', 'e ) 194 cm ²']

Ex Output:
a


Ex Input:
Problem: abcd is a square . e and f are the midpoints of sides cd and bc , respectively . what is the ratio of the shaded region area to the unshaded region ? 
Options: ['a ) 1 : 1', 'b ) 2 : 1', 'c ) 3 : 1', 'd ) 5 : 3', 'e ) 8 : 3']

Ex Output:

d