There are two diagrams showing how the paper interacts with light. In each case, the color of the paper is an indicator of the light color(s) that the paper reflects. You must analyze each diagram to determine if the paper absorbs or reflects each primary color of light.
For instance, one of the diagram shows a single primary color of light being reflected. That is , red light is incident upon the paper and the paper appears red. From this information we can conclude that the paper reflects red light.
The other diagram shows a secondary color of light incident upon the paper. Secondary colors of light (like cyan light) can be thought of as being composed of two primary colors (like blue light and green light). If the paper appears as one of these colors, then that is the color the paper reflects; the other primary color is being absorbed.
Once you have analyzed both diagrams in this manner, you are ready to answer the question. Knowing that cyan pigments absorb red light, magenta pigments absorb green light, and yellow pigments absorb blue light will allow you to draw a conclusion regarding what pigments are in the paper. A sheet of paper that absorbs a single primary color of light contains a single primary pigment. A sheet of paper that absorbs two primary colors of light contains two primary pigments.