Which of the following is true? Group of answer choices 1. The grandfather paradox is a paradox about whether someone can kill their own grandfather 2. The grandfather paradox is a paradox about whether someone kills their own grandfather 3. The grandfather paradox shows that no time travel is consistent 4. The grandfather paradox shows that time travel is impossible

Which of the following is true? Group of answer choices 1. The grandfather paradox is a paradox about whether someone can kill their own grandfather 2. The grandfather paradox is a paradox about whether someone kills their own grandfather 3. The grandfather paradox shows that no time travel is consistent 4. The grandfather paradox shows that time travel is impossible