Question

Jackson’s forces defended themselves by building _[blank]_, which were artificial barricades for military defense

Answer 1

I believe that Jackson’s forces defended themselves by building trenches, which were artificial barricades for military defense.

Answer 2

The answer is earthworks

Step-by-step explanation:

This is correct because of this passage "Jackson scouted a strategic location for a defense. Along a canal, he instructed his men to dig a mile-long ditch. They piled the dirt to form an earthen barrier. The earthworks would serve the Americans well."

Earthworks: (noun) artificial earthen barricades for military defense