We would like you to assess the QUALITY of each of the following argument (discussing Gay Marriage) and determine if the argument is Valid or Invalid. A valid argument is clearly interpretable and either expresses an argument, or a premise or a conclusion that can be used in an argument for the topic of gay marriage. An invalid argument is a phrase that cannot be interpreted as an argument or not on the topic of gay marriage.

Q: What liberals want is a sound argument that proves to them that straight people's rights are being infringed upon.

A: Valid
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Q: There have also been no scientifically documeted cases of gays changing their sexual orientation anymore than straights becoming gay.

A: Valid
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Q: Just as elderly people should not be barred from marrying because they cannot reproduce, so gay people should not be barred from marrying because they cannot reproduce with each other.

A:
Valid
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