Final answer:
The general responsible for the Confederate victory at the First Battle of Bull Run was B) General Stonewall Jackson, noted for his pivotal role in the Confederate defense.
Step-by-step explanation:
The general responsible for the Confederate victory at the First Battle of Bull Run (First Manassas) was neither General Robert E. Lee nor Generals Ulysses S. Grant or William T. Sherman. B) General Stonewall Jackson, whose staunch defense earned him his nickname and played a key role in the Confederate triumph.
In the broader context, the Battle of Bull Run, which occurred on July 21, 1861, in Prince William County, Virginia, marked the beginning of the Civil War's large-scale conflicts. Brigadier General P.G.T. Beauregard, with his forces along Bull Run, and Brigadier General Joseph E. Johnston, commanding additional Confederate forces further west, were the primary Confederate commanders during this battle. While Stonewall Jackson's stand was crucial, Beauregard held the overall command. This clash dashed hopes for a quick Union victory and set the stage for a long and bloody war. It highlighted the Confederates' determination and the Union's underestimation of the Southern forces, leading to a significant shift in Northern strategies and sentiment.