Arthur is a tax preparer doing business as a sole proprietor. Under what circumstances could he receive a pass$-$through deduction that is not limited as a result of it being an SSTB$?$

Only if Arthur were a CPA.

Only if Arthur's business is aggregated with another business that is not an SSTB$.$

Only if Arthur's taxable income does not exceed the applicable threshold.

Only if Arthur's business' QBI does not exceed the applicable threshold.