Question

why was a federal law necessary?
to instruct all health plans to pay any health claim
to simplify billing procedures so services would be paid by check
to mandate that medical bills are transmitted electronically
to force covered entities to cooperate with reduction of expenses

Explanation:

Federal laws related to healthcare often aim to standardize processes. Mandating electronic transmission of medical bills (as in some healthcare - related federal regulations like parts of HIPAA) streamlines the system, reduces errors, and improves efficiency. Paying "any health claim" is too broad and not practical. Simplifying to be paid by check is an outdated and less efficient approach. Forcing entities to cooperate with expense reduction is too vague compared to the specific mandate of electronic transmission which is a key operational aspect.

Answer:

To mandate that medical bills are transmitted electronically.