You are given a background paragraph that describes one or more causal or qualitative relationships such as a relationship in economics or a scientific law and a story that makes use of the concepts or the relationship described in the provided paragraph. You need to come up with a question about the story that requires an understanding of the relationship described in the background paragraph. The generated question should not be answerable without both the background and story. Write a question about the story that requires a relationship in the background paragraph to answer. Check whether your question requires both the background paragraph and the story to answer. If your question can be answered by only one of these, try to rewrite your question so that it requires both. Note that "flipping" a word in the question can give rise to a new question where the answer will be different from the original question. Often, "flipping" a word gives rise to flipping the direction of the relationship, for example, from "increase" to "decrease."

Q: Background Paragraph: The epidermis also contains melanocytes, which are cells that produce melanin. Melanin is the brownish pigment that gives skin much of its color. Everyone has about the same number of melanocytes, but the melanocytes of people with darker skin produce more melanin. The amount of melanin produced is determined by heredity and exposure to UV light, which increases melanin output. Exposure to UV light also stimulates the skin to produce vitamin D. Because melanin blocks UV light from penetrating the skin, people with darker skin may be at greater risk of vitamin D deficiency. 
Story: Jacob has lived in a city in Sweden for most of his life. His favorite hobbies are reading and playing videogames so he rarely goes outside. Even as a kid, he almost never played outside and instead was in his house most of the time. Martin lives in the middle of the Sahara desert in a small town. The sun almost never stops beating down on Martin during the day and it's hard to find shade where he lives.

A: Is Jacob more or less likely than Martin to have a vitamin D deficiency?
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Q: Background Paragraph: Prokaryotes have a different way to increase genetic variation. It’s called genetic transfer or bacterial conjugation . It can occur in two ways. One way is when cells “grab” stray pieces of DNA from their environment. The other way is when cells directly exchange DNA (usually plasmids) with other cells. For example, as shown in Figure below , the donor cell makes a structure called an F pilus , or sex pilus. The F pilus attaches one cell to another cell. The membranes of the two cells merge and genetic material, usually a plasmid , moves into the recipient cell. Genetic transfer makes bacteria very useful in biotechnology. It can be used to create bacterial cells that carry new genes. 
Story: Two researches studied living organisms, Joe studied eukaryotes, while Bill studied prokaryotes. They were fascinated by genetic variation.

A: Which researcher observed fewer cells directly exchange DNA (usually plasmids) with other cells?
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Q: Background Paragraph: One reason radiation is dangerous is that it can’t be detected with the senses. You normally can’t see it, smell it, hear it, or feel it. Fortunately, there are devices such as Geiger counters that can detect radiation. A Geiger counter, like the one in Figure below , has a tube that contains atoms of a gas. If radiation enters the tube, it turns gas atoms to ions that carry electric current. The current causes the Geiger counter to click. The faster the clicks occur, the higher the level of radiation. 
Story: Johnny has two old drums that used to carry nuclear in his garage. He is curious to know about any radiation that the drums are giving off so he purchases a Geiger counter and returns home. Upon returning home, he puts each drum in the opposite corner of his garage and then runs the Geiger counter over the barrel. Drum A causes Johnny's Geiger counter to make a slow but steady noise. When Johnny walks over to Drum B, his Geiger counter starts making rapid sounds. Johnny thinks maybe he should not have invested in these barrels.

A:
Which drum causes less atoms in the Geiger counter to turn into ions?
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