Part II B and II C water quantity criteria address which aspects of water management?

The correct answer focuses on channel protection and flood protection, which are critical components of water quantity management in stormwater systems. Channel protection pertains to the prevention of erosion and damage to stream channels caused by increased runoff from impervious surfaces. This is important because unchecked runoff can lead to significant alterations in the channel's physical characteristics, which can disrupt ecosystems and lead to habitat loss.

Flood protection is equally crucial, as it involves strategies and practices to manage the peak flows of stormwater to prevent flooding in downstream areas. This includes designing systems to retain and gradually release stormwater, thereby mitigating the risk of flooding during heavy rainfall events. Both aspects are vital for maintaining the integrity of waterways and promoting sustainable management practices in urban planning and development.

The other options, while relevant to broader stormwater management and environmental considerations, do not specifically address the primary focus of Part II B and II C, which is on quantity control measures to protect channels and manage flood risks.