题目选项分析

During the same period in which the Maya were developing a hieroglyphic system of writing, the Aztec people also developed a written language, but it was not as highly sophisticated as that of the Maya and was more pictographic in nature.

During the same period in which the Maya were developing a hieroglyphic system of writing, the Aztec people also developed a written language, but, not as highly sophisticated as the Maya's, was more pictographic in nature.