Which sentence has a comma ,begin emphasis,not,end emphasis, used correctly?Answer options with 4 options1.Estuaries contain many living things, birds, fish, insects, and some animals.2.Many estuaries are threatened by land developers who fill in the low, swampy land.3.The balance of nature is upset, and many organisms die.4.Concerned citizens are fighting to save estuaries, but the battle is far from over.