Which of the following component package types have the least parasitic effects at frequencies above the HF range?

At VHF, UHF, and microwave frequencies (above the HF range), the physical wires extending from a component can act as small antennas or unwanted inductors. These unwanted characteristics are known as 'parasitic effects' and can severely degrade the performance of an RF circuit. Surface-mount components (SMD) are placed directly onto the surface of a printed circuit board and soldered to pads without the use of long wire leads. The lack of wire leads drastically minimizes parasitic inductance and capacitance, allowing the circuit to behave predictably at high frequencies. Lead-based packages like TO-220, axial, and radial leads all have physical wires connecting the component body to the board. At microwave frequencies, even a few millimeters of wire can introduce significant inductive reactance, making through-hole components highly unsuitable compared to surface-mount devices.