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Question
X-ray bursters occur in binary star systems. The two types of stars that must be present to make up such an object areA) a white dwarf and a neutron star.
B) a contact binary system of two red giants.
C) a white dwarf and a main-sequence star.
D) a main-sequence or giant star and a neutron star in a mass transfer binary.
E) two neutron stars in a mass transfer binary.
Answer
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