B. Morse created the telegraph in the United States in 1837.
Explanation:
<h3>In the turmoil surrounding the unpopular Vietnam War, lowering the national voting age became a controversial topic. Responding to arguments that those old enough to be drafted for military service, should be able to exercise the right to vote, Congress lowered the voting age as part of the Voting Rights Act of 1970.Jul 1, 1971
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Salt was able to preserve meat before the invention of refrigeration is the correct answer.
