<span>Paradoxically, Saint-Simon both agreed with and
challenged aspects of de Tocqueville's arguments. Saint- Simon wanted to maintain the current way of life, but while arguing for reforms.
Unlike de Tocqueville, Saint- Simon was an advocate (supporter) of a centralised form of government.</span>
The most correct option from those listed here is the second option: The assignment was originally due on Tuesday; however, the instructor changed the due date to Thursday.
The first and third options awkwardly have the word "however" capitalized in the middle of the sentence, and the last option uses the semicolon completely wrong (you're supposed to use it to connect two independent clauses).
Hope this helps. Do let me know if you have further questions.
