In a Labor Market in Which Demand Is Perfectly Elastic

In a labor market in which demand is perfectly elastic and supply is neither perfectly elastic nor perfectly inelastic,who bears a tax if the statutory incidence is placed on the firms?

A) only the workers
B) only the firms
C) both the workers and the firms,although the workers bear more of the tax
D) both the workers and the firms,although the firms bear more of the tax