Prior to the 25th Amendment, the Constitution if the President became temporarily unable to fulfill the duties of office.

A) directed Congress to appoint a President

B) instructed the Vice President to nominate an Acting President

C) charged the Vice President with taking over presidential duties

D) provided no guidelines for what to do

(Gradpoint)

Right choice:

D) provided no guidelines for what to do.

Explanation:

A need to face a situation in which it wasn´t clear what to do to replace a president who can´t fulfill the duties of office prompted the political establishment of Washington to pass the 25th Amendment. Besides, it had to be decided what to do after a vice president left his office vacant if he replaced the president. This happened after Lyndon B. Johnson was sworn in as president following the assasination of John F. Kennedy in 1963, the USA did not have a vice president  for some time.