Carbon deposits on the diffuser and register throat ring of a burner __________.

Correct Answer: Option C — interfere with air flow around the burner

Carbon accumulation on diffusers and register throat rings disrupts optimal air swirl and fuel-air mixing. According to 46 CFR Subchapter F standards for marine boilers, unmitigated buildup distorts combustion air patterns, reducing burner efficiency and risking flame instability or excessive smoke.