Final answer:
The Emancipation Proclamation, issued during the Civil War, would not be considered an event showing tensions that led to the Civil War, unlike John Brown's raid on Harper's Ferry and Bleeding Kansas, which were precursors to the conflict.
Step-by-step explanation:
Among the options given, the event which would NOT be considered as showing tensions that led to the Civil War is (a) The Emancipation Proclamation. The Emancipation Proclamation was an executive order issued by President Abraham Lincoln on January 1, 1863, during the Civil War, thus it came after the conflict had already started. Contrarily, (b) John Brown's raid on Harper's Ferry and (c) Bleeding Kansas were key events that heightened sectional tensions before the Civil War commenced.
John Brown's raid on Harper's Ferry in 1859 was a significant event leading up to the Civil War, illustrating the extent to which some abolitionists were willing to use violence against slavery. Similarly, the term Bleeding Kansas refers to the violent confrontations in the Kansas Territory between proslavery and antislavery factions in the mid-1850s, a direct result of the controversial idea of popular sovereignty where the state's inhabitants would decide whether to allow slavery.
Additionally, in the context of the Compromise of 1850, (b) the admission of Kansas as a free state is incorrect because Kansas was not addressed in the Compromise of 1850; it was later the focus of the Kansas-Nebraska Act of 1854, which applied the concept of popular sovereignty to the region.