Final answer:
Julia explained that the Party restricts sexuality as a means to control people, using puritanism to maintain its power and prevent personal bonds that could threaten its authority.
Step-by-step explanation:
The correct answer to the question of summarizing Julia's explanation of the meaning of the Party's sexual puritanism is B) Julia explained that the Party restricts sexuality to control people. In the dystopian society depicted, the Party imposes strict rules on sexual engagement to maintain power and control over its citizens. This puritanical approach to sexuality is leveraged as a means of social control, ensuring that personal loyalties and bonds do not undermine the Party's authority.