The diagram illustrates an aphid feeding on sugar inside a leaf. As the aphid feeds, what is the sequence in which its mouthparts move through the leaf tissues?
- Apalisade cells $\rightarrow$ phloem $\rightarrow$ upper epidermis
- Bupper epidermis $\rightarrow$ palisade cells $\rightarrow$ phloem
- Cpalisade cells $\rightarrow$ upper epidermis $\rightarrow$ xylem
- Dupper epidermis $\rightarrow$ xylem $\rightarrow$ palisade cells