C) Texas sought to gain independence from Mexico, due to Mexico's government changing from a democracy to a dictatorship.
Texas saw the laws in Mexico as arbitrary and tyrannic in many ways. It reminded them of how British used to treat the colonies, maybe worse. They did not want to follow the rules of Mexico.
They're connected because they both led to the booming production of cotton latter on in the United States after Slater the Trader exposed all secrets of production of the British.