Question

For these four sentences, which sentence order is the most correct?

Answer 1

B. is going to be the best answer because the sentence is structured better than the others. A. doesn't have a good flow. C. sentences usually don't start with the word "But". D. could have made use of punctuation and not use the word "discovery" twice in one sentence. 

Answer 2

D) The discovery that the Universe is expanding was the greatest discovery of the century.