Hello! Nice to meet you. Now let me introduce myself (自我介绍) to you. My name is Mary. I'm 12 years old. I'm from Canada and I speak English. I'm a tall girl. I have long brown hair and big blue eyes. I like music a lot. I often sing songs with my friends in my free time. I have a happy family. There are four people in my family. They are my mom, my dad, my sister and me. I like China very much and I want to visit Beijing, but I can't speak Chinese at all.

    I hope (希望) to be your friend, then we can help each other with English and Chinese.

根据材料内容，选择最佳答案。

甲：连接AC，作AC的垂直平分线MN分别交AD，AC，BC于M，O，N，连接AN，CM，则四边形ANCM是菱形．

乙：分别作∠A，∠B的平分线AE，BF，分别交BC，AD于E，F，连接EF，则四边形ABEF是菱形．

根据两人的作法可判断（   ）