A man can swim with velocity v relative to water. He has to cross a river of width d flowing with a velocity `u (u gt v)`. The distance through which he is carried down stream by the river is x. Which of the following statements is correct?

Options

A. (a) If he crosses the river in minimum time `x= (du)/(v) `
B. (b) x cannot be less than `(du)/(v)`
C. (c) For x to be minimum he has to swim in a direction making an angle of` (pi)/(2)- sin^(-1) (( v)/( u))` with the direction of the flow of water.
D. (d) x will be maximum if he swims in a direction making an angle of `(pi)/(2) + sin ^(-1)(v)/(u) `with direction of the flow of water.