Crime Prevention Through Environmental Design (CPTED) is a proactive design philosophy that uses environmental elements to reduce crime opportunities. One of its core principles is natural surveillance, which involves designing spaces so that legitimate users can easily observe their surroundings. This increases perceived risk for offenders and discourages criminal activity.
A (Balanced systems), B (Protection in depth), and D (Layered defense) are principles used in security system design but not specific to CPTED.
References:
PSP Study Guide - CPTED Principles
POA Manual - Environmental Design and Crime Prevention

Usenet is a global distributed discussion system that predates modern forums and social media. It operates through a network of servers and allows users to post and read messages (articles) in organized newsgroups.
It's one of the oldest forms of online community interaction.
Telnet (B) is a protocol for remote login.
Widespread net (C) and Web net (D) are not recognized technical terms.
References:
PSP Study Guide - Internet-Based Communication Tools
ASIS POA Manual - Networking and Digital Communication Systems

Capacitance proximity sensors detect changes in electrical capacitance, which can be influenced by environmental conditions. Changes in relative humidity can affect the dielectric properties of the air or materials nearby, potentially causing false alarms or degraded performance.
B (Temperature) and C (Air movement) typically affect other sensor types (e.g., infrared or ultrasonic).
D (End-of-line resistance) applies to alarm circuit supervision, not proximity sensing.
References:
PSP Study Guide - Intrusion Detection Technologies
POA Manual - Capacitance Sensor Functionality and Environmental Factors