The correct answer to this open question is the following.
Based on the succession papers submitted by the Southern States to the US Government, the cause of the Civil War was primarily that the Southern states wanted to maintain slavery in their territories. Slavery was at the basis of the Southern economy. Landlords needed slaves to work for long hours in the farm fields to produce the cash crops that had to be traded and exported.
The specific examples from the Texas succession document and the Georgia document are the following.
In the Texan document, it was established that Texas consented to secede and be part of the Confederation to support and promote the welfare of the Texans, maintain internal peace in the state and the prosperity of the people.
In the case of the document of the state of Georgia, it is said that Georgia citizens decided to dissolve their relationship with the Union because they had many complaints against the federal government regarding African American slavery in their farms.