This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Passage: Karl Popper's rejection of Marxism during his teenage years left a profound mark on his thought. He had at one point joined a socialist association, and for a few months in 1919 considered himself a communist. During this time he became familiar with the Marxist view of economics, class-war, and history. Although he quickly became disillusioned with the views expounded by Marxism, his flirtation with the ideology led him to distance himself from those who believed that spilling blood for the sake of a revolution was necessary. He came to realise that when it came to sacrificing human lives, one was to think and act with extreme prudence.
How did Popper's rejection of Marxism in his adult years effect him?