At the first battle of bull run:
a. robert e lee deployed a division of his army to flank the union army led by irwin
mcdowell
b. showcased the timid leadership of the union army of the potomac as caution was the
factor that led to defeat
c. led many to believe falsely that the war would be short since the union achieved a
quick decisive victory
d. the union army led by george mcclellan was able to defeat the southern army led
by general beauregard

Answer:

At the First Battle of Bull Run: C. Led many to believe falsely that the war would be short since the Union achieved a  quick decisive victory

Explanation:

After listening to Scott’s “Anaconda Plan”, many people believed that the war would end quickly as possible because they thought the capture of Confederate capital at Richmond was only one hundred miles south of Washington.

In “Anaconda Plan”, Scott had strategized to subdue the confederate states by first strangling them in the west, by capturing New Orleans, and then blocking the southern ports along with the Eastern and gulf coasts with the help of U.S. Navy. The press had ridiculed Scott when they dubbed his anaconda plan.

it maybe, we dont know. however lucky the lipercon seams guilty