Which of the following is implied by significant population growth on the great plains between 1880 and 1930?
a. more and more land was cleared for farming during this time.
b. dust storms blew away topsoil during this time.
c. many farmers moved to california during this time.
d. there were many years of drought during this time.

The correct answer is A.More and more land was cleared for farming during this time.

As the manifest destiny was still a big thing in the US, people moved more and more westwards and the government supported this by giving them land and letting them have new states and similar things. They would clear large areas so as to have farmers adapt the land for agriculture and make ranches and farms and open businesses.

One of the things that is  implied by significant population growth on the Great Plains between 1880 and 1930 would be "A. More and more land was cleared for farming during this time," since the settlers needed this land. 

The answer would be option a , b, and c.