[Q]: Sentence: The BeiDou Navigation Satellite System (BDS, simplified Chinese: ; traditional Chinese: ; pinyin: Beidou weixing daohang xitong) is a Chinese satellite navigation system. Question: How many satellite constellations does the BeiDou Navigation Satellite System have? OPTIONS:
- yes
- no
++++++++++
[A]: no

[Q]: Sentence: Although blood-letting is no longer in favor with doctors, some leech species are regarded as endangered species because they have been over-harvested for this purpose in the last few centuries. Question: Why are some leeches endangered? OPTIONS:
- yes
- no
++++++++++
[A]: yes

[Q]: Sentence: The use of uranium in its natural oxide form dates back to at least the year 79 CE, when it was used to add a yellow color to ceramic glazes. Question: What was the earliest year in recorded history that uranium oxide was used? OPTIONS:
- yes
- no
++++++++++
[A]:
yes