Which story line primarily concerns external conflict

First of all we need to know that the external conflict means that the main character is fighting with external problems. Such as robot vs robot, robot vs man, etc.An example of this is Romeo and Juliet. In this play,  the two title characters fall deeply in love but are from feuding families. Their struggle to be together is external, as it is between the two lovers and society's pressures for them to hate one another.  It is in fact this struggle with their society that actually causes the tragic deaths of both title characters.

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Iwould say a but i don’t know what words are underlined