According to the us constitution, federal election laws regulate which of the following

The correct answer is the election of members of Congress.

There is an Elections Clause considered as the main source of constitutional authority to regulate elections for the U.S. Senate and House of Representatives. This clause contains everything to organize congressional elections like voter registration, prevention of fraud, and results.

The Constitution is specific in the residency, citizenship, and age requirements of the candidates who want to content for the Senate or the House of Representatives.  

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