Federal system maintain close relation between the gorvnment and the people justify the statement

Federalism can eliminate the problems of the system, and in a federal system power is shared between the central government and state government. Similarly, people have the rights to choose the state and central government and they can vote for their candidates to run the governance.

Explanation:

answer; i believe the correct answer is (a) the correlation between the cause variable and outcome variable is zero;

can you explain a little further maybe give multiple choice? ?