In fig.
`anglePOR and angleQOR` form a linear pair if `a -b = 80^@` then values of a and b are :

Options

A. `a=130^@,b=50^@`
B. `a=50^@,b=130^@`
C. `a=60^@,b=120^@`
D. `a=40^@,b=140^@`.