In the mid-1900s, developed a classification system to treat World War II soldiers that had a significant influence on the creation of the first DSM.

The US Army and Veterans' Administration

Explanation: The DSM, which is called the Diagnostic and Statistical Manual of mental disorder was developed from data collected by psychiatric hospitals and census. However the first Diagnostic and Statistical Manual for mental disorder mainly evolved from the classification system devolved by the U. So army and Veterans' Administration to treat soldiers affected during the second world War. The Diagnostic and Statistical Manual for mental disorder is now being adopted by psychiatric drug regulation agencies, pharmaceutical companies, health insurance companies and so on.

brainliest is someone you pick by simply clicking a button. it only shows up if there are two people that answered your question, then you decide who answer more accurately with detail and explanation and you give that person the title "brainliest".

i hope this your understandings.

a. theta waves. this is because the person is in a light sleep which means the brain waves would show these kind of waves.