Which of the following is a PG binder tested for low temperature properties?

The selection of -22°C as a Performance Grade (PG) binder tested for low temperature properties is correct because it reflects the established criteria for evaluating how asphalt binders perform in colder climates. The designation of PG binders incorporates various temperature ranges to ensure that the asphalt performs optimally under both high and low temperature conditions.

In this context, testing for low temperature properties is crucial as it addresses the binder's ability to resist cracking and maintain flexibility when subjected to cold weather. The specific value of -22°C indicates that this binder can withstand low temperatures down to that threshold without compromising its structural integrity. This is particularly important for regions that experience severe winter conditions, ensuring that the asphalt pavement remains durable and serviceable.

The other temperature choices do not specifically align with the defined performance characteristics for low-temperature PG binders that are typically utilized in various highway and pavement specifications. These binders are crucial for ensuring that pavements remain functional and safe during cold weather conditions.