What is the term for an arrangement of signals and signal appliances that must succeed each other in the proper sequence?

The term that describes an arrangement of signals and signal appliances that must succeed each other in the proper sequence is "interlocking." This concept is crucial in railroading, as it ensures that signals are set and activated in a predetermined order to maintain safety and prevent conflicting movements. Interlocking systems prevent trains from being given signals that could lead them into dangerous situations by ensuring that signals can only be activated when it is safe to do so. This mechanical or electronic safety procedure enables efficient traffic control on the rail networks, ensuring smooth operation and reducing the likelihood of accidents.

The other options do not specifically address the necessity of signals succeeding each other in a sequence. Signalization refers broadly to the use of signals, while sequencing and control systems do not inherently imply the arrangement aspect specific to interlocking systems. Hence, interlocking is the most precise term for the described arrangement.