Answered

Sumner was physically attacked by Brooks in Congress because ___________________ .

ASumner had attacked abolitionists in Congress.
CSumner had berated pro-slavery, popular sovereignty supporters.
BSumner supported the border ruffians in the Kansas Territory.
DSumner challenged the Fugitive Slave Act and angered pro-slavery supporters.

Verified Answer :

Sumner was physically attacked by Brooks in Congress because "d. Sumner challenged the Fugitive Slave Act and angered pro-slavery supporters" since he was an avid abolitionist. 

Answer:

C). Sumner had berated pro-slavery, popular sovereignty supporters.

Explanation:

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