What does they mean as stated in the last paragraph

Me will give brainliest and dont just answer for the brainliest bc im only gonna give it to you if your right what is the best way to combine sentence 6 and sentence 7? question 5 options: for instance, the wright brothers dreamed of being able to fly, but they decided to invent the airplane. for instance, the wright brothers dreamed of being able to fly; the wright brothers decided to invent the airplane. for instance, the wright brothers dreamed of being able to fly, they decided to invent the airplane. for instance, the wright brothers dreamed of being able to fly, so they decided to invent the airplane.