Answer:
Winston suggests that the Egyptians' math was far more advanced than previously thought.
Explanation:
The sentence above is the one among the others that makes use of proper punctuation and capitalization.
Proper nouns (Winston and Egyptians) are capitalized, the use of possession (Egyptians') was also well punctuated and the sentence also ends with a period (.) which shows that it was the end of the sentence.
The other options all have punctuation and/or spelling defects.