When Was the Concept of Third-Party Payments and Prepaid Health

When was the concept of third-party payments and prepaid health insurance instituted?

A) at the turn of the 20th century in the lumber and mining camps of the Pacific Northwest
B) during World War I for families of those serving in the armed services
C) during the Depression by Blue Cross/Blue Shield to provide reimbursement to subscribers
D) in 1935 as part of federal legislation to establish Social Security