According to regulations, what condition must be maintained for B-quality eggs?

B-quality eggs must meet specific criteria to ensure their suitability for various uses while being distinct from higher-grade eggs. One of the key characteristics of B-quality eggs is that they must be clean and free of significant blemishes. This requirement is important because it helps maintain a certain standard for eggs that are not intended for premium markets but still need to be safe and acceptable for consumption or processing.

While size, shell color, and the presence of restrictions might pertain to other grades or categories of eggs, the emphasis on cleanliness and the absence of blemishes for B-quality eggs is vital in the regulatory framework. Compliance with these standards helps prevent contamination and ensures the eggs are still viable for their intended purposes, whether for cooking, baking, or other industrial uses. Thus, option C reflects the correct understanding of the condition that must be maintained for B-quality eggs.