What U.S. amendment extended civil rights?

Answer 1

Most of them
Amendments 1-10 established most civil rights
The 13th ended slavery
The 14th required equal protection & application of all rights and law
The 15th banned denying of rights based on race
The 19th ensured women the right to vote
The 24th eliminated poll taxes (which was designed to prevent poor people from voting)
The 26th Allowed 18 year olds, subject to taxes and conscription, the right to vote.

So of 27 amendments, 16 of expanded civil rights

Answer 2

Make that 17. The 21st amendment extended the right to be able to sell, manufacture, distribute, and imbibe alcohol.