I would personally do one. I wouldnt have the time do two. But if theres a rare case of asking two related texts, ill just use my other module's related and just shape the analysis to answer the question correctly.
For both AOS and Mod C I have two relateds prepared but only 1 paragraph for each so I'm not in the position to use just one -- so I would use two definitely.
In the case the ask for just one I just write both paragraphs anyway and just pretend they came from the same text