A main indicator of the spread of homelessness during the Great Depression was ...

A. bread lines.

B. westward migration.

C. Hoovervilles.

D. unemployment.

I believe the answer is: Hoovervilles

Hoovervilles is a residential area which made by using scrap metals and other cheap material which commonly used by Hobboes During the Great Depression.

Increasing number of hoovervilles indicate that the number of unemployed people because of the great depression aslo increased, which make it a good indicator for economic measurement

A main indicator of the spread of homelessness during the Great Depression was " C. Hoovervilles," since this were shanty towns that were built for people who had lost their original homes.