Given the task definition and input, reply with output. This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

Apollo and his sister Artemis can bring death with their arrows. The conception that diseases and death come from invisible shots sent by supernatural beings, or magicians is common in Germanic and Norse mythology. In Greek mythology Artemis was the leader (, "hegemon") of the nymphs, who had similar functions with the Nordic Elves. The "elf-shot" originally indicated disease or death attributed to the elves, but it was later attested denoting stone arrow-heads which were used by witches to harm people, and also for healing rituals.
Who is Apollo's sister?