Answer:
C.flagellum, lysosome
Step-by-step explanation:
Flagellum and lysosome are the most appropriate structures for providing positive identification of an animal cell under a microscope.
Flagellum are thin filaments, formed by microtubules in their central portion, that allow the cell to swim by liquid means. Usually a flagellate cell has only one flagellum, which can average 200 µm in length and 0.2 µm in diameter. Flagellum are structures located in some specific cell types, which would help to identify a cell.
Lysosomes are organelles present in the cytoplasm of the vast majority of eukaryotic cells, which facilitates their identification. Inside the lysosomes we can find a lot of digestive enzymes.