Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Nobody really has such colorful eyes! The colors were added digitally after the photo was taken. They represent all the different colors of light. Light is a form of energy that travels in waves. Light of different colors has different wavelengths. Answer: wavelengths

A: Different colors of light differ in terms of which important attribute?
****
Q: Passage: Plasma cells are activated B cells that secrete antibodies. Antibodies are large, Y-shaped proteins that recognize and bind to antigens. Plasma cells are like antibody factories, producing many copies of a single type of antibody. The antibodies travel throughout the body in blood and lymph. Each antibody binds to just one kind of antigen. When it does, it forms an antigen-antibody complex (see Figure below ). The complex flags the antigen-bearing cell for destruction by phagocytosis . Answer: antibodies

A: What do you call large, y-shaped proteins that recognize and bind to antigens?
****
Q: Passage: Dirt that gets on our hands can be difficult to remove by rinsing with cold water. What are some things that you can do to increase the solubility of dirt, making it easier to dissolve in running water?. Answer: solubility

A:
Increasing what property of dirt would make it easier to rinse off your hands?
****