Pick out the wrong statement.

A. With decrease in feed temperature, the number of plates required for binary distillation decreases for a given L/V ratio

B. The extraction per unit of total height for a short packed column is more effective than for a tall column, in case of liquid-liquid extraction

C. Natural draft cooling towers are made of ferro-concrete and its cross-section is wider at the bottom

D. Vanderwall adsorption is also called chemisorption

Answer: Option D