The extension of slavery into the western territories.
For a specific instance, see the landmark supreme court case Dred Scott v. Sandford.
Answer:
The last option because it is the first action in the order
Explanation:
Alexander had previously prepared takeover by defeating the Persian army at Issus and captured the Mediterranean eliminating the threat of a Persian naval invasion. As well as keeping Persian land reinforcements from coming from the West, which was key in focusing on other points.
The battle itself against the saxons making England his own.
