A pipe of I.D. 4 m is bifurcated into two pipes of I.D. 2 m each. If the average velocity of water flowing through the main pipe is 5 m/sec, the average velocity through the bifurcated pipes is__________________?
A. 20 m/sec
B. 10 m/sec
C. 5 √2 m/sec
D. 5 m/sec