This is true. When you choose between two things, the thing that you didn't choose is what cost you the thing you chose. It's called an opportunity cost and it presents what you had to lose or give up in order to attain the thing that you chose and assessing these costs is extremely important in decision making.
The answer is b, because they are trying to change them to how they seem fit
1.
The Confederates won
2.
<span>The First Battle of Bull Run (called First Manassas in the South) cost some 3,000 Union casualties, compared with 1,750 for the Confederates. Its outcome sent northerners who had expected a quick, decisive victory reeling, and gave rejoicing southerners a false hope that they themselves could pull off a swift victory. In fact, both sides would soon have to face the reality of a long, grueling conflict that would take an unimaginable toll on the country and its people.</span>
I believe your answer is C)
The president was given power by the U.S. Constitution to veta or sign/pass a bill.
Hope this helps
~Onyx~