The correct answer is number 3) "These women and men faced the discomforts of weightlessness and overcame them."
The topic sentence of this paragraph from "Life Without Gravity" is "These women and men faced the discomforts of weightlessness and overcame them."
When we talk about a topic center, we are looking for the most important sentence in a paragraph. This sentence, when written correctly- summarizes the meaning or the important idea of the paragraph. The topic sentence maintains the direction of the paragraph. So when writing an essay, remember the importance of your topic sentence.
To identify the central idea of the text readers must - Engage while reading so that they comprehend what the writer is trying to communicate!
Hope it helps!
XD
It is the first one because it just gives better details