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The Quantum Oracle Classification (QOC) problem is to classify a function, given only quantum black box access, into one ofÌýseveral classes without necessarily determining the entire function. Generally, QOC captures a very wide range of problems inÌýquantum query complexity. However, relatively little is known about many of these problems.ÌýIn this work, we analyze the a subclass of the QOC problems where there is a group structure. That is, suppose the range of theÌýunknown function A is a commutative group G, which induces a commutative group law over the entire function space. Then weÌýconsider the case where A is drawn uniformly at random from some subgroup A of the function space. Moreover, there is aÌýhomomorpism f on A, and the goal is to determine f(A). This class of problems is very general, and covers several interestingÌýcases, such as oracle evaluation; polynomial interpolation, evaluation, and extrapolation; and parity. These problems areÌýimportant in the study of message authentication codes in the quantum setting, and may have other applications.ÌýWe exactly characterize the quantum query complexity of every instance of QOC with group structure in terms of a particularÌýcounting problem. That is, we provide an algorithm for this general class of problems whose success probability is determined byÌýthe solution to the counting problem, and prove its exact optimality. Unfortunately, solving this counting problem in general is aÌýnon-trivial task, and we resort to analyzing special cases. Our bounds unify some existing results, such as the existing oracleÌýevaluation and parity bounds. In the case of polynomial interpolation and evaluation, our bounds give new results for secretÌýsharing and information theoretic message authentication codes in the quantum setting.