Consider the following statements 1. Wind speed is influenced by the topographical features. 2. The effect of surface friction extends to a height of about 500m (1650 ft) 3. Rougher surfaces produce more friction. 4. Wind speed changes according to pressure gradient. Which of the above statements is/are correct?

Consider the following statements 1. Wind speed is influenced by the t

1.	Consider the following statements 1. Wind speed is influenced by the topographical features. 2. The effect of surface friction extends to a height of about 500m (1650 ft) 3. Rougher surfaces produce more friction. 4. Wind speed changes according to pressure gradient. Which of the above statements is/are correct?
A.	1 and 2only
B.	1, 2 and 3 only
C.	1, 2, 3 and 4
D.	2, 3 and 4 only
Answer» D. 2, 3 and 4 only