Public speaking has been formally studied since:
a. the 5th century.
b. the 20th century.
c. recently.
d. communication courses were offered at universitie

A. the 5th century.

Explanation:

The early study of public speaking was known as rhetoric.

It was first developed in the Classical period of ancient Greece, around the 5th century BC. Traditional rhetoric included insights and rules created by rhetors to train the citizens of the Greek republics and, eventually, the descendants of the rich during the Roman Empire, in the art of public speaking.

a, c, & d are correct:

they wanted lands to settle the extra population.

they wanted new markets for english goods.

they wanted to avoid civil war.