ANS:B - Toor and Marchello

I'm not familiar with any significant figures or works in chemical engineering or related fields named "Toor and Marchello." It's possible that they may have contributed to the field in some capacity, but without additional context, it's challenging to provide a detailed explanation. If you could provide more information about who Toor and Marchello are or what specific contributions or works you're referring to, I'd be happy to try to help further!