The constitutional question at the heart of United States v. Nixon is best described as

Correct answer is: C. The degree to which the separation was permitted.

Explanation:

The United States of America v. Nixon (1974). Richard Nixon was charged with being involved in Watergate Scandal (1972). Watergate Scandal is a break-in at the headquarters the Democratic National Committee that revealed how the Nixon administration had repeatedly abused its power.

Although the President was asked for the documents and the uncut tape recordings related to the incident, he refused. He claimed that he had a legal right to withhold data of other government agencies. Richard Nixon had to submit evidence after the Supreme Court ruled that executive privilege was not sufficient. In the end, the President resigned.