Q. Which of the following statement is wrong ?

• (A) Energy dissipaters are provided for small discharges
• (B) The siphon fall is designed to maintain a fixed supply level in the channel
• (C) The energy dissipation takes place by the provision of roughening devices
• (D) In a trapezoidal notch fall, the top width of the notch is kept between 3/4th to full water depth above the sill of the notch