instruction:
In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
question:
Which of the following is not the title of a leader: president, emperor, or Chihuahua?, Context: Under threat from the conservative forces, Governor Terrazas was deposed, and the state legislature proclaimed martial law in the state in April 1864 and established Jesús José Casavantes as the new governor. In response, José María Patoni decided to march to Chihuahua with presidential support. Meanwhile, Maximilian von Habsburg, a younger brother of the Emperor of Austria, was proclaimed Emperor Maximilian I of Mexico on April 10, 1864 with the backing of Napoleon III and a group of Mexican conservatives. Before President Benito Juárez was forced to flee, Congress granted him an emergency extension of his presidency, which would go into effect in 1865 when his term expired, and last until 1867. At the same time, the state liberals and conservatives compromised to allow the popular Ángel Trías take the governorship; by this time the French forces had taken control over the central portions of the country and were making preparations to invade the northern states.
answer:
Chihuahua


question:
Who ruled Bithynia before Bas?, Context: The Bithynians were a Thracian people living in northwest Anatolia. After Alexander's conquests the region of Bithynia came under the rule of the native king Bas, who defeated Calas, a general of Alexander the Great, and maintained the independence of Bithynia. His son, Zipoetes I of Bithynia maintained this autonomy against Lysimachus and Seleucus I, and assumed the title of king (basileus) in 297 BCE. His son and successor, Nicomedes I, founded Nicomedia, which soon rose to great prosperity, and during his long reign (c. 278 – c. 255 BCE), as well as those of his successors, the kingdom of Bithynia held a considerable place among the minor monarchies of Anatolia. Nicomedes also invited the Celtic Galatians into Anatolia as mercenaries, and they later turned on his son Prusias I, who defeated them in battle. Their last king, Nicomedes IV, was unable to maintain himself against Mithridates VI of Pontus, and, after being restored to his throne by the Roman Senate, he bequeathed his kingdom by will to the Roman republic (74 BCE).
answer:
Calas


question:
What is the use of fungus Aspergillus niger?, Context: Chromobacterium violaceum and Pseudomonas fluorescens can both mobilize solid copper, as a cyanide compound. The ericoid mycorrhizal fungi associated with Calluna, Erica and Vaccinium can grow in copper metalliferous soils. The ectomycorrhizal fungus Suillus luteus protects young pine trees from copper toxicity. A sample of the fungus Aspergillus niger was found growing from gold mining solution; and was found to contain cyano metal complexes; such as gold, silver, copper iron and zinc. The fungus also plays a role in the solubilization of heavy metal sulfides.
answer:

solubilization of heavy metal sulfides