Which of the following frequencies are used for digital communicator handshakes?

The correct answer identifies the specific frequencies commonly utilized for digital communicator handshakes in alarm systems. Digital communicators rely on specific signaling frequencies to effectively transmit information between the alarm system and monitoring stations. The frequencies of 1400 Hz and 2300 Hz are well-established in the industry for this purpose. Dual tone signaling is effectively used in communication protocols, enabling the transmission of data and facilitating reliable, two-way communication during the handshake process. This ensures that the alarm system can confirm connection and transmission status, enhancing overall system functionality.

The other options present frequencies that may not align with the standard specifications used for digital communicator handshakes, thereby making them unsuitable choices for this question. Understanding the accurate frequency values used in alarm communication is crucial for individuals involved in the installation, service, and monitoring of these systems.