Which concept in OOP explains the relationship between the classes Nation and President, where the class Nation has-a (an) object of class President? A.
aggregation
B.
association
C.
abstraction
D.
composition
E.
inheritance

Choose the best explanation for the following statement communication is symbolic

Need asap write a short paper describing the history and differences between six sigma, waterfall, agile, and scrum models. understanding these models can give you a good idea of how diverse and interesting it development projects can be. describe what the rationale for them is and describe their key features. describe the history behind their development. at least 400 words

Which demographic challenge is europe currently experiencing? a. an aging and decreasing population b. a baby boomc. an unequal distribution between males and females d. a large group of teenagers moving through the school system(i chose a but i'm unsure)