Every day after school, Carla and I would study for our math class. One day while walking home, Carla said, "I won't be able to study our math assignments with you anymore. my family is moving to Hillsborough, and I'll be going to another school." We were both sad and tearful, but then I had an idea. We could still study together using the Internet at home.

What type of error can be found in the paragraph above?

A. spelling
B. usage
C. punctuation
D. capitalization