Answer:
He shows a concern with the system of checks and balances
Step-by-step explanation:
We can see that Mason is concerned about the junction between executive and legislative powers that the vice president may cause. This shows that he is concerned with the system of checks and balances.
This system states that the government should be divided into three powers, the legislative, the executive and the judiciary. Each of these powers is present separately, but in agreement with each other. In addition, each power must inspect the other, which is why it is dangerous to unite them.