Read the following article and answer the question. Article: Have you ever dreamed about sending a letter to yourself or your friends in the future ? While express mail representing efficiency and speed is prevalent in China , there is another type of mail appearing as a new business : " Future Mail " . " Future Mail " service can make people slow down and let them understand the meaning of " time " in another way . And " Future Mail " letters are " reminders of affection , friendship and love ". Lin Xiaofan , a senior high school student in Hefei , wrote a letter to her mother in advance to express her love to her mother for next Mother's Day . Feng Xiao , a youth who feels pressure despite of some achievements in her career decided to write a letter to herself on her 25th birthday and have it delivered five years later on her 30th birthday through a " Future Mail " . She expressed her thoughts about her present life and her expectations for the future to encourage herself to face up to the challenges of her life with courage . While " Future Mail " is gaining popularity , some people are concerned about what happens if the postal address of the receiver changes or if the company goes broken before letters are delivered . Actually , customers required to complete an acceptance form and make an assessment so they can be _ if their letters or goods are lost or damaged . Most of the business's customers are college students and young white-collar workers . Psychologists said young Chinese might be given a vent to their negative feelings through the service . Most people put their hopes and wishes in the letters so they can experience the connection between " past " and " present " while they receive the letters . It can help people reunderstand the meaning of " time " . Question: Which is NOT the purpose of Feng Xiao's letter ? Answer:
Options:
--To encourage herself to face up to the challenges .;
--To express her thoughts about her present life .;
--To express her expectations for the future .;
--To remind herself of something she must do .;
To remind herself of something she must do .