Why are black people so black?

At noon, seven-year-old Niu Niu's family of five sat around the dining table. There are several plates of freshly cooked jiaozi in front of them, steaming like white fog.

Grandma brought five saucers from the kitchen, and Niu Niu scrambled to set them for everyone, then went to get vinegar and soy sauce bottles, so that grandparents, parents and parents could pour soy sauce and vinegar into the saucers according to their own tastes, and Niu Niu came last. Niu Niu poured soy sauce first, but because she didn't control it well, she poured a full plate of soy sauce and spilled it on the table.

The mother on one side said, "Niu Niu, do you want to be black?"

Niu Niu stretched out her tongue and made a face at her family. She seemed to suddenly wake up and say to everyone, "I know why black people are so dark?"

"Why?" The family asked curiously in unison.

"I think black countries are rich in soy sauce, all of which are soy sauce factories. Eating soy sauce is cheap and convenient. Because I ate too much soy sauce, my skin was so dark. " Niu Niu imitates the teacher's lecture posture and pretends to say.

The whole family laughed, and grandparents even burst into tears.

Then, my mother was afraid that Niu Niu's cognition was wrong, and she especially corrected it: "Niu Niu, your statement is a joke, completely wrong!" " The real reason why blacks are black is not because they eat too much soy sauce, but because their country is located above the equator. You will learn it in geography class in the future. The most popular saying is that they are too close to the sun overhead, and the high temperature and ultraviolet rays from the sun are too strong. After a long time, their skin will naturally become black. "

Niu Niu stared at a pair of big eyes for knowledge and nodded clearly. "Now, I really know why black people are so black!" "