In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.

Q: Question: Could a glass electrode be used as a reference electrode ?: 
 Options:  <0> Yes, if the glass electrode is a combined electrode. <1> Yes, if a mercury electrode is used as the indicator electrode. <2> No, since the glass electrode is a selective electrode. <3> No, because its foundation is not Nerstian. <4> Yes, if the determination is made in a buffered medium.

A: chemistry
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Q: Question: The solubility of copper hydroxide in the presence of a high concentration of ammonia: 
 Options:  <0> Increased by formation of a complex ion of Cu2 + with NH3. <1> It is not affected because there is no common ion effect. <2> Decreases by common ion effect. <3> It decreases upon oxidation of bromide to molecular bromine. <4> It decreases because the hydroxides are more soluble in acidic medium.

A: chemistry
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Q: Question: Pseudomonas aeruginosa is typically: 
 Options:  <0> Sensitive to most antibiotics used in human medicine. <1> Pathogen obligated. <2> Opportunistic pathogen. <3> Commensal bacteria of the digestive tract. <4> Intracellular pathogen.

A:
biology
****