Which defect would be categorized under "other causes"?

The categorization of defects in commodities is often based on the underlying causes of damage or quality issues. "Other causes" typically refer to defects that do not fall under more common or easily identifiable categories. In this context, sunburn is considered a defect that arises from environmental conditions affecting the commodity but does not fall into the typical categories of frost damage, insect damage, or mechanical injury.

Sunburn on agricultural products, particularly fruits and vegetables, occurs when they are exposed to excessive sunlight, leading to discoloration or compromised quality. This type of damage is sometimes seen as more of a physiological response rather than a direct physical or pest-related injury, which is why it fits the "other causes" classification.

In contrast, frost damage refers specifically to harm caused by low temperatures, insect damage results from pests that feed on or infest the commodity, and mechanical injury is linked to physical handling or transport issues. These are defined defects with clear causes that fit better into specific categories, leaving sunburn as the most appropriate example of a defect typically classified under "other causes."