B. This contradicts Tolkien's supposed idea of "subcreation", by which God delegates aspects of creation to creatures. But, as Aquinas explains in SCG II.21, there can be no instrumental causes in the act of creation. So much for that. Of course, it's more likely that this whole "subcreation" business is just a misconstrual of Tolkien's intent. What the Valar (forgive the extreme nerdiness of this discussion) do doesn't obviously involve the creation of prime matter out of nothing, but the forming from some preexisting being ("Eä") of particular objects with specific natures (plants, trees, mountains, dwarves, etc.). The inability of the Valar to "subcreate" is made clear by the fact that the dwarves are effectively beasts until the divinity intervenes and gives intelligent (and therefore subsistent) souls.
C. "Moreover, according to the Philosopher, “it is the office of a wise man to set things in order.” For things can be ordered only by knowing their relation and proportion to one another, and to something higher, which is their end; for the order of certain things to one another is for the sake of their order to an end. But only a being endowed with intellect is capable of knowing the mutual relations and proportions of things; and to judge of certain things by the highest cause is the prerogative of wisdom. All ordering, therefore, is necessarily effected by means of the wisdom of a being endowed with intelligence. Even so, in the world of the mechanical arts, the planners of buildings are called the wise men of their craft. Now, the things produced by God have a mutual order among themselves which is not fortuitous, since this order is observed always or for the most part. That God brought things into being by ordering them is thus evident. Therefore, God brought things into being by His wisdom." — SCG II.24.4