Pick up the correct statement from the following

A. Approach of the water line in a flumed channel section should not be steeper than $$22{\frac{1}{2}^ \circ }$$

B. Departure of the water line from a flumed channel section should not be steeper than 30°

C. Approach of the water line should not be steeper than 30° and departure line not steeper than $$22{\frac{1}{2}^ \circ }$$ in a flumed channel section

D. Approach and departure of the water line in a flumed channel section, should not be steeper than $$22{\frac{1}{2}^ \circ }$$

Answer: Option C