Here's a short story:

Nick and his friends were talking about things that can bring them luck . "I have a lucky red pen," said Andrea. "I have a lucky penny ," said Manuel. Every time I want to do really well in tests, I carry my lucky penny." Nick thought for a moment, and answered, "My blue socks." "Blue socks?" the boys were surprised and asked together. Nick said that every time he wore his blue socks to school before a test, he got a good mark. The next day Nick would have a Chinese test. He was sad because he couldn't find his blue socks to wear to school. "Mom!" shouted Nick. "Where are my blue socks? I will have a Chinese test, and I need to wear them." "Don't be silly," Nick's mom said. "They need to be washed." "When I wear them, I get a good grade," Nick said. "Did you prepare for your test?" asked Mom. "Yes." "Then don't worry about it. Just do your best," Mom encouraged. Nick was worried about his test because his lucky socks would not help him. A few days later, Nick's teacher told him that he got 95 in his test. Nick was so excited that he couldn't wait to tell Mom how well he did in his test. Mom said, "It wasn't the blue socks that made you successful. It was made by yourself." (End of story)

Provide your best guess for the following question. Give ONLY the guess, no other words or explanation.

For example:

Guess: <most likely guess, as short as possible; not a complete sentence, just the guess!>

Here are a few examples of questions and answers:

Question: What was everyone talking about?
Guess: things that can bring them luck

Question: Who had the penny?
Guess: Manuel

Question: Does it help him in school?
Guess: yes

Question: Does Andrea have a pencil?
Guess: No

Question: What does she have?
Guess: A red pen

Now answer the following question in the same format.

Question: Why was Nick worried?

he couldn't find his blue socks to wear to school