Which of the Following Trends Has Started Years Ago in the U.S

Which of the following trends has started years ago in the U.S. healthcare sector and now can be observed in the Polish healthcare industry as well?

A) Use of predetermined reimbursement rates and limits on the number of services by public insurers.
B) Increased consumer cost-sharing as a tool to reduce moral hazard.
C) System-wide trend to actively encourage substitution of hospital care with other, less expensive treatment modalities.
D) Prominence of employer-sponsored private health insurance.
E) Mandatory insurance for all workers.