Which of the Following Statements Explains the Conflict That Exists

Which of the following statements explains the conflict that exists between Congress and the president in institutional terms?

A) It is the result of the rise of political parties in the aftermath of the adoption of the Constitution.
B) It is the result of the fact that president and Congress are often members of different political parties.
C) It is the result of the shared nature of power between Congress and the executive branch.
D) It is the result of the unitary nature of the executive branch, which gives presidents absolute control over the policy agenda in American politics.
E) It is the result of fact that the Constitution locates the office of the vice president in both the executive branch and the legislative branch.