Never. The SAT is a "closed universe" exam. An answer is only correct if the provided text explicitly supports it. Even if a passage claims something factually "wrong" in the real world, you must treat the passage as the ultimate truth. 

Search for "Poison Words." There are often distractors that are 90% accurate but contain one extreme qualifier (e.g., always, never, only) or a slight shift in tone. 

If a single word is unsupported, the entire choice is wrong. Use Process of Elimination to find reasons to kill an answer. 

Focus on the task. 

"Main Purpose" asks why the author wrote the piece (look for action verbs like to challenge or to illustrate). 

"Central Idea" asks what the text is actually saying (look for a summary of the content). Don’t trade a "what" for a "why." 

Ignore the choices initially. 

Read the two sentences and identify their logical hinge: are they contrasting (Flip), expanding (Plus), or concluding (Result)? 

Once you identify the relationship, find the word that matches your label. 

You are likely ignoring the Goal. These questions provide a list of notes and a specific instruction (e.g., "The student wants to emphasize the scale of the project"). 

The correct answer isn't just a "true" statement from the notes; it is the only one that achieves that specific underlined goal.