Final answer:
According to Bowen's reaction series, orthoclase feldspar and olivine can occasionally be found together in an igneous rock, making option d) orthoclase feldspar and olivine the correct pair that you would likely find together.
Step-by-step explanation:
According to Bowen's reaction series, the minerals that crystallize from a magma do so in a predictable order. This series is divided into two branches, one for mafic (rich in magnesium and iron) and another for felsic (rich in silica) minerals. Minerals that crystallize at higher temperatures in the mafic branch, like olivine and pyroxene, are rarely found in the same igneous rock as minerals that crystallize at lower temperatures in the felsic branch, such as quartz and muscovite.
Therefore, among the options given, a) quartz and olivine, b) muscovite and olivine, and c) Ca-plagioclase feldspar and olivine, the most unlikely pair to be found together in the same igneous rock would be quartz and olivine, or muscovite and olivine because they crystallize at significantly different temperatures. Olivine is typically found in ultramafic or mafic rocks like peridotite or gabbro, while quartz and muscovite are typically found in felsic rocks such as granite or rhyolite.
The correct answer to which pair of minerals you would likely find together in an igneous rock, based on Bowen's reaction series, is option d) orthoclase feldspar and olivine. Orthoclase feldspar and olivine can occasionally be found together in the same rock because orthoclase feldspar can form at a higher temperature than quartz and muscovite, and there may be some overlap in the temperature range of crystallization with olivine.