<prompt> Sequence of colour changes observed in Raynauds disease: September 2009, March 2012Red, blue, whiteWhite, blue, redBlue, red, whiteWhite, red, blue  <response>: Ans. B: White, blue, red The change in skin color is caused by the constriction or narrowing, or spasm of blood vessels in the finger, toes, and earlobes. This causes blood flow to the area be reduced, and the skin color to turn white pallor. When the oxygen supply to the area is depleted, the skin color turn blue cyanosis. When blood return to the area, the skin color turn red rubor. The symptoms of Raynauds Disease are: Color change in the fingers, toes, and earlobes when exposed to cold or stress When warmed, the skin color turns back to normal Burning, tingling and pin-and-needles sensation during color change In rare, severe cases, gangrene can develop at the tip of the fingers 