A 47 Ω resistor is in series with an inductive reactance of 120 Ω across an ac source. The impedance, expressed in polar form, is

• A. 47 ∠68.6° Ω
• B. 120 ∠68.6° Ω
• C. 129 ∠31.4° Ω
• D. 129 ∠68.6° Ω