Fine, it is up to her whether or not to provide DNA to silence the critics.
But if she chooses not to then they can choose not to be silent. This is now the ninth year since Obama's have left office and I don't see anyone being being silenced (except for Joan Rivers). It is completely in her power to silence them and she has chosen not to.
As a result if you don't like these questions, then blame Michelle Obama for not silencing them.
In a court of law she is not required to respond, but in the court of public opinion she is.
Also, if she wished she could sue, but if she did that they would then have the right to demand the DNA evidence. Perhaps the reason she doesn't sue is because she is afraid of a court order for her DNA.
You're a clown if you think she's obligated to respond to baseless allegations by ignorant bigots like you.
Also she's an attorney so she knows she wouldn't win a defamation lawsuit because it hasn't actually caused her any damage
You have a cartoonish understanding of the law if you think someone can collectively Sue everyone on the internet for saying something stupid