Final answer:
Multiple factors, including substance abuse, mental illness, physical disabilities, and economic conditions, contribute to homelessness.
Step-by-step explanation:
There are multiple reasons why people become homeless. One-third of the homeless have substance abuse problems, another third are mentally ill, and about a quarter have a physical disability. Many homeless individuals are also veterans or victims of domestic abuse. Economic conditions, such as recessions or rising rental prices, can also contribute to homelessness.