In poultry terminology, what is a critical feature of U.S. Grade A birds?

In poultry terminology, U.S. Grade A birds are recognized for their superior quality, and a critical feature of this grade is that they must not show any exposed flesh. This requirement indicates that the birds are well-prepared for market, exhibiting a high standard of appearance and quality. Exposed flesh can suggest poor handling or processing practices, which would compromise the overall quality of the meat. Grade A designation is highly desirable as it reflects the best in terms of presentation and consumer expectations.

The other options reflect characteristics that do not align with the standards of U.S. Grade A. For instance, small blemishes are typically associated with lower grades, while a significant amount of fat is more often a characteristic of specific cooking styles or preferences rather than an indicator of quality grade. Also, the age of the bird, while relevant to certain classifications, does not specifically determine whether a bird can be graded as U.S. Grade A.