Wall painting also called mural painting is a fom of painting done on walls. It can be done on outside walls, and very much of recent, indoors. Mural painting takes a lot of skills and techniques to master. Some types are done on dry plaster, while some are delicately done on wet plaster. In most mural painting, binding agents in the form of egg white and other binders are usually used to hold the paint to the walls. Some mural painter have to have a combined knowledge of wall plastering, printing press (some mural painting are printed and attached to the wall), and architecture in order to get the job done right.
Reject most closely means "to dismiss." The choice "to throw away" would describe how the writer is completely against the idea that he or she is too young to make a difference and "dismisses", disregards and does not accept the idea that he or she is too young to make a difference. -E :)