Why Did the DRI Committee Not Set an Upper Level

Why did the DRI committee not set an Upper Level for fiber? 

A)  A body can never have enough high-fiber foods. 
B)  High-fiber foods are so filling, they are not likely to be eaten in excess. 
C)  There are no consequences to an abundance of high-fiber foods. 
D)  Fiber benefits everyone's GI tract, so the more fiber, the healthier the digestive system. 
E)  There was not enough evidence regarding fibers effects on health.