If white is called black, black is called red, red is called yellow, yellow is called green, green is called blue, blue is called violet and violet is called orange, what would be the colour of human blood?

This is a logical substitution puzzle.

If:

• White → Black
• Black → Red
• Red → Green
• Green → Blue
• Blue → White

Then what is the color of blood?

• Blood is Red normally
• But 'Red' is now called Green

Hence, the answer is Green.