Final answer:
The three words to complete the quotation about Scrooge seeing himself older may describe early signs of aging, and while the exact words cannot be provided without the specific passage, terms like care, worry, and avarice are likely to fit the context of his character in 'A Christmas Carol'.
Step-by-step explanation:
The quotation is from Charles Dickens' A Christmas Carol, in which the character Ebenezer Scrooge is visited by various spirits who show him scenes from his past, present, and possible future. The three words that complete the quotation "For again Scrooge saw himself. He was older now; a man in the prime of life. His face had not the harsh and rigid lines of later years; but it had begun to wear the signs of" are likely to be reflective of Scrooge starting to show early signs of aging, such as care, worry, and avarice, correlating with his character's development in the story.
Without the exact passage from Dickens' text, we cannot provide the verbatim three words that would complete this specific quotation. However, Dickens often portrayed Scrooge as a man whose life of greed and a lack of compassion aged him prematurely. Examples from similar descriptions in literature often include terms that would fit the context provided.