Answer: Della laments that she will, soon, lose her most precious possession.
Explanation: The inference that the reader can best make about Della's actions based on the excerpt from "The Gift of the Magi" by O. Henry is Della laments she will, soon, lose her most precious possession. Della is proud of her hair that reaches below her knee. It is like an ornament for her. It's Christmas Eve, and in order to buy a present for Jim, Della is going to sell her hair. She laments that she has to sell her most precious possession.