Which of the Following Statements Is True? the Burden of a Payroll

Which of the following statements is true? The burden of a payroll tax is paid:

A) by workers if the demand for labour is perfectly inelastic.
B) by firms if they are legally responsible for remitting the tax to the government.
C) by both workers and firms if the elasticities of demand and supply of labour are between zero and infinity.
D) by workers if the supply of labour is perfectly elastic.
E) indeterminate.