Use a disfluent question or a proper question and find the answer to the question based on the given context or return None if an answer can't be found. A disfluent question is a question that has some interruptions in it while framing. A proper question is the correct form of the question without any disfluency.
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Question: proper question: What city did the Grand Canal never reach during the Yuan? 
 disfluent question: What city did the Grand Canal never reach during Kublai Khan no I mean during the Yuan? 
 context: The Yuan undertook extensive public works. Among Kublai Khan's top engineers and scientists was the astronomer Guo Shoujing, who was tasked with many public works projects and helped the Yuan reform the lunisolar calendar to provide an accuracy of 365.2425 days of the year, which was only 26 seconds off the modern Gregorian calendar's measurement. Road and water communications were reorganized and improved. To provide against possible famines, granaries were ordered built throughout the empire. The city of Beijing was rebuilt with new palace grounds that included artificial lakes, hills and mountains, and parks. During the Yuan period, Beijing became the terminus of the Grand Canal of China, which was completely renovated. These commercially oriented improvements encouraged overland and maritime commerce throughout Asia and facilitated direct Chinese contacts with Europe. Chinese travelers to the West were able to provide assistance in such areas as hydraulic engineering. Contacts with the West also brought the introduction to China of a major food crop, sorghum, along with other foreign food products and methods of preparation.

Answer: None


Question: proper question: What happens because younger rock is deeper? 
 disfluent question: What are thrust faults formed I mean happens because younger rock is deeper? 
 context: When rock units are placed under horizontal compression, they shorten and become thicker. Because rock units, other than muds, do not significantly change in volume, this is accomplished in two primary ways: through faulting and folding. In the shallow crust, where brittle deformation can occur, thrust faults form, which cause deeper rock to move on top of shallower rock. Because deeper rock is often older, as noted by the principle of superposition, this can result in older rocks moving on top of younger ones. Movement along faults can result in folding, either because the faults are not planar or because rock layers are dragged along, forming drag folds as slip occurs along the fault. Deeper in the Earth, rocks behave plastically, and fold instead of faulting. These folds can either be those where the material in the center of the fold buckles upwards, creating antiforms, or where it buckles downwards, creating synforms. If the tops of the rock units within the folds remain pointing upwards, they are called anticlines and synclines, respectively. If some of the units in the fold are facing downward, the structure is called an overturned anticline or syncline, and if all of the rock units are overturned or the correct up-direction is unknown, they are simply called by the most general terms, antiforms and synforms.

Answer: None


Question: proper question: What do simple unicellular organisms lack? 
 disfluent question: What do pathogens no no um simple unicellular organisms lack? 
 context: Pathogens can rapidly evolve and adapt, and thereby avoid detection and neutralization by the immune system; however, multiple defense mechanisms have also evolved to recognize and neutralize pathogens. Even simple unicellular organisms such as bacteria possess a rudimentary immune system, in the form of enzymes that protect against bacteriophage infections. Other basic immune mechanisms evolved in ancient eukaryotes and remain in their modern descendants, such as plants and invertebrates. These mechanisms include phagocytosis, antimicrobial peptides called defensins, and the complement system. Jawed vertebrates, including humans, have even more sophisticated defense mechanisms, including the ability to adapt over time to recognize specific pathogens more efficiently. Adaptive (or acquired) immunity creates immunological memory after an initial response to a specific pathogen, leading to an enhanced response to subsequent encounters with that same pathogen. This process of acquired immunity is the basis of vaccination.

Answer:
None