Arthur sells $100 worth of cotton to Bob. Bob turns the cotton into cloth, which he sells to Camille for $300. Camille uses the cloth to make prom dresses that she sells to Donita for $700. Donita sells the dresses for $1,200 to kids attending the prom. The total contribution to GDP of this series of transactions is:_______.
A. $1200.
B. $500.
C. S2300.
D. $1100.