The correct answer is Walking over land bridges, i took the test.
They were all slave states that had remained in the Union and this is what Missouri, Kentucky, Maryland and Delaware had in common during the Civil war. The correct option among all the options that are given in the question is the second option. I hope that this is the answer you were looking for and it helped you.
Martin Luther King Jr was against racism
Explanation:
The unprecedented levels of production in domestic manufacturing and commercial agriculture during this period greatly strengthened the American economy and reduced dependence on imports. The Industrial Revolution resulted in greater wealth and a larger population in Europe as well as in the United States.