Final answer:
The model where every government level is involved in implementing policies is known as cooperative federalism, where federal and state governments work together to tackle national problems.The correct option is e.
Step-by-step explanation:
The model in which every level of government is involved in implementing a policy is referred to as cooperative federalism. In cooperative federalism, both the federal and state governments coordinate their actions to solve national problems, leading to a blending of governance layers similar to a marble cake. This model contrasts with dual federalism, where the state and national governments operate in distinctly delineated spheres of jurisdiction, and competitive federalism, where states compete with each other in various policy areas. Cooperative federalism rose from the need to address large-scale issues that affected the entire nation, such as the Great Depression and civil rights movement.