10. The reaction \text { 4Al }(\mathbf{s})+3 \mathbf{O}_{2}(\mathbf{g}) \rightarrow 2 \mathbf{A} \mathbf{2} \mathbf{O}_{3}(\mathbf{s}) \quad \Delta \mathbf{H}^{\circ}=-3351 \mathbf{k J} is ______and therefore heat is by the reaction. A) endothermic, released B)

endothermic, absorbed C) exothermic, released D) exothermic, absorbed E) thermoneutral, neither released nor absorbed