Part A- Answer C
Part B- Answer D
Nasa is realising a new idea that Will help humanity build a better state of wafare but this May lead to a down fall on pigs production because it will effect the food chain it will kill of all the McDonald's chain and it may become a major change in history so become the next time you to out of house and wear a t-shirt because children might be around.
The topic sentence is, of course, a sentence where you state the main topic of your paper. You want people to know your topic as soon as possible. Therefore, answers A and D are obviously places you would most commonly put your topic sentence. However, you can also put it in your body of your paper. But the one place you never want to put your topic sentence is answer C, in your conclusion paragraph.