Sentence:  But after the doctor 's return that night Alex could see , from the high window in his own room , the now familiar figure crouched on a truly impressive heap of towels , apparently giving its egg hatching <WSD>powers</WSD> one final chance before it was replaced in its office by a sure-enough hen . 
Meaning of the word marked with <WSD> tags:  possession of the qualities (especially mental qualities) required to do something or get something done