**CONCEPT: The question tests the basics of Geometry(Circle).**

**SOLUTION: **

Given ∏R2 =R

=> R = 1/∏ =7/22

(Now we know 1/22 as a percentage is 4.16 and hence 7/22 will be 4.16*7 = 29.12%)

Closest option as a decimal is (b) as (a) is anyhow smaller than 29.12 and the rest of the options are very far from 29.12%)

**OPTION B**