Teacher:In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
Teacher: Now, understand the problem? Solve this instance: Problem: radius of a circle is 5 cm , if we draw a rectangle of maximum size , what is the area of rectangle ?
Options: ['a ) 30', 'b ) 40', 'c ) 50', 'd ) 60', 'e ) 70']
Student:
c