Choose the sentence that best describes the overlap between argumentative and persuasive texts.
both text types always recognize the existence of opposing opinions.
both text types force the reader to adopt the author’s viewpoint.
both text types use rhetorical techniques to support a particular viewpoint.
both text types use bias and persuasive techniques to sway the audience.

In an argumentative and persuasive texts, both definitely use rhetorical techniques to support a particular viewpoint. although all choices are good; in my opinion, this one's the best description because a person can not hope to make their point across to their audience without using multiple rhetorical devices and they absolutely can't persuade their audience to see their point without using any rhetorical device. 

Rhetorical device/technique: is a use of language that is intended to have an effect on its audience.

so if you hope to have an effect towards your audience through argumentative and persuasive texts, rhetorical devices/techniques are highly recommended.