Geology is the science of Earth.
Ecology is the science of relationship between an organism and its environment.
Astronomy is the science of studying astronomical objects.
Whereas, Phrenology is the study of relating the size of human skull like its size, shapes e.t.c to his/her personality. So, its not a science as there is no scientific relationship between it.
Acceleration is when something is being moved forward or back, motion is just movement, friction is two or more things rubbing together, so the answer should be B. gravity
