Is a recessive genetic disorder that strikes young african-americans and affects the hemoglobin in red blood cells. a) aids b) hemophilia c) tuberculosis d) sickle-cell anemia

answer; ///(b) it is composed of four protein chains and four heme groups;

that would be called plucking : )

explanation:

''plucking, also referred to as quarrying, is a glacial phenomenon that is responsible for the erosion and transportation of individual pieces of bedrock, especially large "joint blocks". as a glacier moves down a valley, friction causes the basal ice of the glacier to melt and infiltrate joints (cracks) in the bedrock."