Final answer:
A synthetic web sling is characterized by its resistance to corrosion, which is a notable advantage over metal alternatives.
Step-by-step explanation:
The characteristic of a synthetic web sling that is relevant to the choices provided is its resistance to corrosion. Synthetic materials such as nylon or polyester, commonly used in the construction of web slings, are known for their ability to resist corrosion, especially when compared to metal alternatives. However, synthetic web slings are not generally known for high heat tolerance, and while they may have some resistance, they are not particularly characterized by their conductivity or UV radiation resistance.