Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Resistors connected end to end are said to be in series.

Answer: Resistors connected end to end are said to be in what?


Question: When an atom gains or loses an electron it becames a(n) ion.

Answer: When an atom gains or loses an electron it becames an?


Question: The composition of the atmosphere has changed over the last 200 years primarily due to human activity.

Answer:
Which of the following has changed over the last 200 years primarily due to human activity?