What needs to be done to correct the following sentence?

Queen Mary wanted her death to be remembered,therefore,she staged a pageant.

A. Change the comma after remembered to a semicolon.

B. Change the comma after remmbered to a semicolon and add a comma after Mary.

You wrote:

What needs to be done to correct the following sentence?

Queen Mary wanted her death to be remembered, therefore, she staged a pageant.

A. Change the comma after remembered to a semicolon.

B. Change the comma after remmbered to a semicolon and add a comma after Mary.

Changing that one comma to a semicolon is a given. The question is whether there should be a comma after "Mary" -- and there should not. You never want to separate a subject from its verb with a comma. Here is a good webpage that explains comma uses: http://grammar.ccc.commnet.edu/grammar/commas.htm
You'll not find a single one of those reasons that justifies using a comma after the subject of a clause or sentence.

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