Yes. Context matters. The meaning conveyed here is “Which are not primary sources about war or historical event that they are describing?” Anyone answering under that assumption (with the right relative answers) is correct. They get bonus points if they subtly disambiguate the question by including gratuitous “are primary sources about X” so that their words are literally correct not matter how poorly you are communicating.
Yes. Context matters. The meaning conveyed here is “Which are not primary sources about war or historical event that they are describing?” Anyone answering under that assumption (with the right relative answers) is correct. They get bonus points if they subtly disambiguate the question by including gratuitous “are primary sources about X” so that their words are literally correct not matter how poorly you are communicating.