This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

[Q]: Passage: According to Sun Jiadong, the chief designer of the navigation system, "Many organizations have been using our system for a while, and they like it very much." Question: What did Sun Jiadong have to say about the BeiDou navigation system?
[A]: "Many organizations have been using our system for a while, and they like it very much."


[Q]: Passage: In February 1861, secessionists in Tennessee's state government—led by Governor Isham Harris—sought voter approval for a convention to sever ties with the United States, but Tennessee voters rejected the referendum by a 54–46% margin. The strongest opposition to secession came from East Tennessee (which later tried to form a separate Union-aligned state). Following the Confederate attack upon Fort Sumter in April and Lincoln's call for troops from Tennessee and other states in response, Governor Isham Harris began military mobilization, submitted an ordinance of secession to the General Assembly, and made direct overtures to the Confederate government. The Tennessee legislature ratified an agreement to enter a military league with the Confederate States on May 7, 1861. On June 8, 1861, with people in Middle Tennessee having significantly changed their position, voters approved a second referendum calling for secession, becoming the last state to do so. Question: Which area of Tennessee was most resistant to secession?
[A]: East Tennessee


[Q]: Passage: The synthesis of urea by Friedrich Wöhler opened a new research field, organic chemistry, and by the end of the 19th century, scientists were able to synthesize hundreds of organic compounds. The later part of the 19th century saw the exploitation of the Earth's petrochemicals, after the exhaustion of the oil supply from whaling. By the 20th century, systematic production of refined materials provided a ready supply of products which provided not only energy, but also synthetic materials for clothing, medicine, and everyday disposable resources. Application of the techniques of organic chemistry to living organisms resulted in physiological chemistry, the precursor to biochemistry. The 20th century also saw the integration of physics and chemistry, with chemical properties explained as the result of the electronic structure of the atom. Linus Pauling's book on The Nature of the Chemical Bond used the principles of quantum mechanics to deduce bond angles in ever-more complicated molecules. Pauling's work culminated in the physical modelling of DNA, the secret of life (in the words of Francis Crick, 1953). In the same year, the Miller–Urey experiment demonstrated in a simulation of primordial processes, that basic constituents of proteins, simple amino acids, could themselves be built up from simpler molecules. Question: What scientific act is Friedrich Wohler known for?
[A]:
The synthesis of urea