<span>Option C.) colloquialisms.
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It seems that you didn't include the whole excerpt, given that the last sentence abruptly stops in the middle. However, the <span>phrases in this excerpt from Robert Stawell Ball's Great Astronomers that convey a commendable tone toward Ptolemy’s work are found in the last (incomplete) sentence: </span><span><u>Ptolemy is, without doubt, the greatest figure in ancient astronomy. </u>
Commendable means praise-worthy. </span>
It should be D. Thesis sentences are giving you an overview of how your essay is going to unfold. Then with each point your backing up a topic sentence which is that point; with examples and explanations to explain said point.