What structural modification of the small intestine slows the movement of chyme through the lumen?

Circular folds are structural modification of the small intestine slows the movement of chyme through the lumen..

"Early hypotheses were not tested by experimentation" is the one way among the choices given in the question that early scientific practice differed from modern scientific practice. The correct option among all the options that are given in the question is the second option. I hope the answer helps you.