Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
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Question: Finally, in 2001, SV Nord-Nordstern and SC Wedding-Rapide came together to form SV Nord Wedding 1893.

Answer: What year did SV Nord Wedding 1893 dissolve?

Question: The 1873 Victorian football season was an Australian rules football competition played during the winter of 1873.

Answer: What's 1873 Victorian football season sport?

Question: During 1970 and 1971, I discovered that a devastating disease of potato plants is not caused by a virus, as had been assumed, but by a new type of subviral pathogen, the viroid. Viroids are so small--one fiftieth of the size of the smallest viruses--that many scientists initially doubted their existence. We now know that viroids cause many damaging diseases of crop plants. Fortunately, new methods that are based on the unique properties of viroids now promise effective control.

Answer:
Which are the smallest known subviral pathogens of plants?