Answer:
In adittion to replacing the president iff necessary, it's duty of the vice president to: C. preside over the senate.
Step-by-step explanation:
To understand this answer we need to review all of the options.
a.- The house elects its speaker so this is incorrect.
b.- The vice-president doesn't serve as the liaison to the judicial branch. The judicial branch liaisons with the president are chosen by him and the vice-president is not one of them.
c.- The vice-president can preside over the senate however his or her role doesn't have a breakpoint vote power.
d.- This is incorrect, laws pass to the senate before the president. Then he or she reviews them by himself or herself.