[单选题]
A force moves an objec aziegp *7m jzax/38ov65/trct in the direction of the force. hv4xfxob5 0pk:*ic5d The graph in Fig. 6-1 shows the force v5pkc xbdo4*v xf:5i0h ersus the object's position. Find the work done when the object moves from 0 to 6.0 m.
A. $20 \; J$
B. $40 \; J$
C. $60 \; J$
D. $80 \; J$
