The subjects that both of these exceprts address is time.
C. time
Explanation:
<em>In the excerpt from ¨Ode on a Grecian Urn¨ by John Keats. Figuratively "old age" is here to "waste" an entire generation of people which happens to be the narrator’s generation. The narrator is imagining that after everyone in his generation is dead and the urn will still be around. Tima and old age can be one and the same. </em>
<em>In the second excerpt from Ozymandias, Ozymandias brags about his "works", he's referring to the numerous colossal statues of him, such as the statue described in the poem. </em>
<em>Ozymandias is telling the "mighty" to "despair", saying something like ¨Don't get your hopes up¨ because your statues, accomplishments, power, etc. will eventually be destroyed or fade away, with nothing to show for them but an ancient statue, half-buried in the sand dunes.</em>