Hybrid h-parameters — match each parameter to its unit List I (h-parameter) A. h_ie (input impedance with output shorted) B. h_oe (output admittance with input open) C. h_fe (forward current gain with output shorted) List II (Unit) 1. siemens (S) 2. no units (dimensionless) 3. ohms (Ω)

Introduction / Context:
The hybrid (h-parameter) model is a popular small-signal representation of bipolar junction transistors. Correct units reinforce physical meaning: impedance in ohms, admittance in siemens, and current gain as dimensionless.

Given Data / Assumptions:

• Common-emitter h-parameter definitions: h_ie, h_oe, h_fe.
• Small-signal (incremental) linearization applies around a bias point.

Concept / Approach:
By definition: h_ie is an input impedance (V/I) → ohms; h_oe is an output admittance (I/V) → siemens; h_fe is a ratio of currents (ΔI_c/ΔI_b) → dimensionless. Recognize that “e” subscript denotes the common-emitter configuration and the “i/o, e/f” letters indicate input/output and impedance/admittance or current/voltage relationships.

Step-by-Step Solution:

Verification / Alternative check:
Dimensional analysis of the hybrid equations v1 = h11 i1 + h12 v2 and i2 = h21 i1 + h22 v2 confirms the unit assignments for the corresponding elements.

Why Other Options Are Wrong:

• Swapping ohms and siemens reverses impedance/admittance meanings.
• Assigning units to a pure gain ratio (h_fe) is incorrect.

Common Pitfalls:
Memorizing symbols without understanding that “ie” and “oe” encode which port and which type of quantity is being referenced.

Final Answer:
A-3, B-1, C-2