Final answer:
The subject of this question is fencing, and the outrigger is a type of additional fencing often used on top of chain link fencing for added security and prevention of climbing or unauthorized access.
Step-by-step explanation:
The subject of this question is fencing. Fencing is a technique used to enclose an area, typically using materials like wood or metal. In this specific case, the question mentions chain link fencing and a standalone outrigger, which suggests the use of additional fencing on top of the chain link fence. This additional fencing is called an outrigger, which is often used to provide extra security and to prevent climbing or unauthorized access.