单项选择题
Your letter arrived on Monday. I didn’t answer it at once, because I had an important test this week. We are very happy that you’re coming to stay with us. Perhaps you’ll find it exciting when you first come to China, for you’ll be doing a tot of new and interesting things. School life here will be quite different from that in the U. S. , but I am sure you’ll soon get used to it here.
The writers didn’t answer the letter immediately because(). A．he had to prepare for a test
B．he refused to answer it
C．he couldn’t read it