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Studies of the Allende meteorite provided information about the composition of chondritic meteorites and their possible origin. A. When Allende entered Earth's atmosphere, it broke into thousands of pieces called chondrites because they look like glassy, black seeds. B. Chondrules are tiny, millimeter-sized drops of silicate materials that probably formed when lumps of nebular dust were fused at extremely high temperatures and then quickly cooled. C. The matrix that holds the chondrules and inclusions together in Allende consists mainly of grains of nebular dust that were trapped inside the meteor before they could be melted. D. The mineral content of chondrules suggests that they were probably formed in isolated regions of the nebula that remained much hotter than the rest. E. Irregularly shaped inclusions in Allende are composed of minerals that are resistant to melting and are believed to be the earlest minerals to have condensed out of the nebula. F. Except for being depleted in volatile elements, chondritic meteorites are probably very similar in composition to the matter from which planets were assembled.