Four persons K,L,M,N are initially at the four corners of a square of side d. Each person now moves with a uniform speed v in such a way that K always moves directly towards L, L directly towards M, M directly towards N, and N directly towards K. The four persons will meet at a time............. .

Options

A. `(d)/(v) sec`
B. `(sqrt(2d))/(v) sec`
C. `(d)/(sqrt(2v))sec`
D. `(d)/(2v) sec`

Answer

A