Which sentence uses a formal writing style?

some people really want to get up in space, so now there's a market for space tourism.
we can't all be astronauts, but lots of us dream about the idea of space travel.
there was an article that told about how seven people got to make space flights.
a company plans to make space flights available to those who can afford the ticket price.

the answer is c because info security should not use them for code

invention of the washing machine

in the past, people used sticks and stones or scrub boards to clean their clothing. as it was sweaty, backbreaking work, we owe a world of to james king because he created the model for the modern washing machine in 1851. the most important issue was that this machine cleaned clothes while a person cranked the handle. doing this made people who used it develop strong muscles in their arms. later, in 1908, alva j. fisher created an electric washing machine named thor. this one was not the first automatic washing machine. however, it was one of the most popular models at the time.