A.I. Explanation:

Option 1: "Differing opinions on slavery contributed to the Civil War."

Explanation: The text discusses how the resolutions regarding slavery created a divide within the Democratic Party and led to significant events such as the Republican victory and the Civil War. This indicates that differing opinions on slavery were a key factor in the conflict.

Option 2: "The North expected and demanded the Civil War."

Explanation: This option misrepresents the text. The North's resentment towards pro-slavery demands is mentioned, but it does not imply that they expected or demanded the Civil War; rather, it suggests a reaction to the demands.

Option 3: "The radical southern states instigated the Civil War."

Explanation: While the text mentions the secession of radical southern states, it does not state that they instigated the Civil War. The focus is on the broader context of differing opinions on slavery leading to the conflict.

Option 4: "Disputes between political parties had little effect on the Civil War."

Explanation: This option contradicts the text, which highlights the significant impact of political disputes, particularly between the Democratic and Republican parties, on the events leading to the Civil War.