A. Choose the best answer（根据以下内容，选择最恰当的答案）
April 13th, 1539
Outside Mexico City
Dear Mariana,
Today we arrived safe. It was a long and dangerous trip over the ocean. The winter storms were strong. We were always a little sick from high waves.
The journey from the shore to Mexico City is also long and dangerous. There are robbers in the countryside. We will travel together with the other ship passengers, thinking we will be safer as a group. Tomorrow we will travel into the city to find our uncle.
Father says it will take a year for this letter to reach you. The trip from New Spain to Spain is very long.
Your loving brother,
Tomas
April 20th, 1539
Mexico City
Dear Mariana,
Father and I finally arrived at Mexico City. Here, old buildings are being pulled down; new ones are being built. Just around the corner from Uncle's city house, Aztec workers are pulling down a small, beautiful pyramid. Father says it is one of the last Aztec temples.
In the center of the city, I met an Aztec boy named Carlos. He speaks a little Spanish. Carlos learns Spanish at his new school. He told me that the Spanish set up new schools for the Aztecs. There he got his new name, Carlos. He says he likes his new school but misses his old city. I wonder what this city used to be like before Cortes came.
Tomorrow we will go to Uncle's farmland. He and father are talking about the Aztec workers that father will oversee.
Your brother,
Tomas
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