The worst tornado swept through Missouri, killing many people...

Hello, everyone.
The worst tornado (1) _______ through the states of Missouri, Illinois, and Indiana in 1925, (2) ________ 689 people.
A. (1) swept - (2) killing B. (1) sweeping - (2) killed

The key is A. (1) swept - (2) killing
But I think B. is correct, too. Because we can say the same sentence like:
The man standing there was my brother.
Could you please give me some advice on this?
Thank you.

The worst tornado swept through the states of Missouri, Illinois, and Indiana in 1925, killing 689 people.[YSaerTTEW443543]

TOEIC listening, talks: Radio commercial for an invisible dog fencing system[YSaerTTEW443543]

The comma after “1925” is wrong with “sweeping/killed”. If you deleted the comma then “sweeping/killed” would be possible, and would refer to the worst tornado in those states in 1925 (rather than the worst tornado over some longer period of time and potentially larger area).

The man who stole my bicycle was Mary’s brother.

=> The man stealing my bicycle was Mary’s brother. => correct or not?

Thanks.

Pioneers, _________ in isolated areas of the United States, were almost totally self-sufficient.
A. who living
B. living
C. lived
D. who lived

Which option is correct? Thanks.

It depends on the question, but I doubt it because of the mix of tenses in your answer.

The man stealing my bicycle is Mary’s brother - present
The man who stole my bicycle was Mary’s brother - past

With the comma after ‘pioneers’ D is correct.
Without the commas, B would be correct.