Answer: The right answers are:
1) A person's face = "[...] a shattered visage."
2) Regions with relation to their weather patterns = "Of cloudless climes and starry skies."
3) A side of the body = [...] "silken flanks."
Explanation: Just to elaborate a little on the answer, it can be added that in the sentence "and all her silken flanks with garlands drest [...]" the speaker is referring to one of the pictures of the Greek urn that he is praising. In that picture, a young cow is about to be sacrificed. She is mooing, and her silken legs, or flanks, are decorated, or dressed, with flowers. A person's face can also be more poetically referred to as the visage. In the line "Half sunk, a shattered visage lies, whose frown [...]" the speaker is referring to a statue, specifically that of the Egyptian pharaoh Ramesses II - Ozymandias. Finally, the phrase "Of cloudless climes and starry skies" is a reference to weather patterns, which the speaker of Lord Byron's famous poem uses in order to compare it to the beauty of a specific woman.
