Which color is not present in 5 Olympic rings?

This is a trick question because the five Olympic rings plus the white background actually include six colors, and every major color you might think of is either in the rings or the background, but the color that is not present is often considered to be orange, purple, or any color other than the six official colors. The five interlocking rings are blue, yellow, black, green, and red, displayed on a white background. Those six colors including white were chosen by Pierre de Coubertin in 1913 because at least one of those colors appears on the national flag of every country in the world at that time, symbolizing universality. So colors like orange, purple, pink, brown, or gray are not present in the Olympic rings logo. If the question asks which of the standard primary colors is missing, the answer is that all primary colors blue, yellow, and red are present, plus green and black. The white background is technically the sixth color. The IOC has strict brand guidelines that prohibit changing the colors or adding other colors to the official rings. Sometimes people mistakenly think one of the continents is missing a color, but the rings do not represent specific continents with specific colors; the colors are not assigned to continents, they are simply a universal palette. So any color outside blue, yellow, black, green, red, and white is not present.