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

Problem: the area of rectangular field of length 90 meters and breadth 80 meters is equal to the area of a square plot . what will be the length of the diagonal of the square plot ?
Options: ['a ) 100 m', 'b ) 120 m', 'c ) 95 m', 'd ) 80 m', 'e ) 150 m']
b