Answer:
Some scientists are for a manned mission to Mars while some are against a manned mission to Mars. People should think about it.
Explanation:
In the given statements, the sentences contain different aspects of what scientists are for. While the first presents them in one aspect, the next present them in the opposing aspect.
So, in order to rewrite or re-frame the given passage/ sentences, we can connect the two first statements as they are related to one another even though they may have opposite or contrasting opinions/ aspects.
Thus, the correct way to rewrite or revise the sentences for fluency will be-
<em><u>Some scientists are for a manned mission to Mars while some are against a manned mission to Mars. People should think about it.
</u></em>
