I generally wish that the agencies would offer a little more accurate information when sending rejection reasons. Instead of, your pic. was rejected because of this or possibly this. What? Does the reviewer not know the reason?
Huh! Ok lets try that again. Cat or cats? Back to our favourite subject of keywording. If you have a photo of a cat, ie. one solitary feline friend. Do you just enter the singular of the word or the plural also?