How Is Workers' Compensation Usually Funded

How is workers' compensation usually funded?

A) by a tax levied on employers by state governments based on the employer's average monthly number of employees
B) by contributions to a pool of funds by organizations in the same industry which purchase insurance for the employers as a group
C) through state value-added taxes on goods sold and manufactured
D) by insurance purchased by employers from a private carrier or state insurance fund or by self-insurance