Which of the following roofing types is the most appropriate for installation during below-freezing weather...

Comprehensive and Detailed Explanation From Exact Extract:

Low-slope roofs (< 2:12) require roofing materials suitable for flat or nearly flat conditions:

Cold-tar built-up roofs (A) are difficult to install in freezing weather because the tar cannot be applied or cured properly in cold temperatures.

Self-sealing shingles (B) are generally used on steeper slopes and depend on heat to activate the sealing strips, making them unsuitable for low slopes and cold weather.

Ballasted EPDM (C) is a single-ply synthetic rubber membrane that can be installed in a variety of weather conditions, including below-freezing temperatures. The ballast (usually gravel) holds the membrane in place on low slopes and does not rely on adhesives or heat curing.

Therefore, ballasted EPDM is the most appropriate.