MOS logic families terminology: What do P-MOS and N-MOS designate in the context of MOS logic families?

Introduction / Context:
Before CMOS dominated mainstream logic, single-polarity MOS families were widely used. These families implemented logic using only one conduction type—either P-channel devices (P-MOS) or N-channel devices (N-MOS)—along with load devices, rather than complementary pairs.

Given Data / Assumptions:

• P-MOS: logic built primarily from P-channel transistors with suitable loads.
• N-MOS: logic built primarily from N-channel transistors with suitable loads.
• CMOS (complementary MOS) uses both P-channel and N-channel devices in complementary pairs.

Concept / Approach:
P-MOS and N-MOS designate single-polarity MOS logic styles. These styles have different speed and power characteristics from CMOS. N-MOS became popular due to higher electron mobility (faster than P-MOS at similar geometries). CMOS ultimately supplanted both by providing low static power and symmetrical drive using complementary devices.

Step-by-Step Solution:

Verification / Alternative check:
Historic microprocessors (e.g., early generations) were implemented in N-MOS technologies before transitioning to CMOS as processes matured.

Why Other Options Are Wrong:

• 74HC: A CMOS family, not single-polarity MOS.
• Positive/negative MOS for differential supplies: Not a standard classification.
• “None of the above” and “analog switches only” ignore long-standing single-polarity logic implementations.

Common Pitfalls:
Confusing P-MOS/N-MOS with CMOS; assuming “N-MOS” implies always modern low-power behavior (it does not compared to CMOS); forgetting that thresholds and speed/power differ from CMOS families.

Final Answer:
Represent MOSFET devices utilizing either P-channel or N-channel devices exclusively within a given gate