Why do parris and abigail tell susanna to "speak nothing of unnatural causes"?

Read the excerpt from frederick douglass’s speech “what to the slave is the fourth of july? ”go where you may, search where you will, roam through all the monarchies and despotisms of the old world, travel through south america, search out every abuse, and when you have found the last, lay your facts by the side of the everyday practices of this nation, and you will say with me, that, for revolting barbarity and shameless hypocrisy, america reigns without a rival. what is one way that douglass achieves his purpose of persuading the reader to see his point of view? by relating as many facts and statistics to the reader as possibleby using familiar and casual language to make the reader feel comfortableby using gentle language to evoke a sense of calm and tranquilityby repeating the word “you” to directly relate to the reader