If you do not know whether a new worker is an employee or an independent contractor:

a) you must treat the worker as an employee.

b) you must treat the worker as an independent contractor.

c) you may seek a determination from the IRS on classifying the person, but until the IRS responds you must treat the worker as an employee.

d) you may seek a determination from IRS on classifying the person, but until the IRS responds you must treat the worker as an independent contractor.

Please do explain your answer.