Which organisms can be classified under the term "vectors"?

Vectors are organisms that transmit pathogens and diseases from one host to another, playing a critical role in the spread of diseases. The correct choice includes organisms such as rodents and mosquitoes, which are well-documented vectors for various infectious diseases.

Rodents can carry and spread bacteria and viruses, such as hantavirus and leptospirosis, while mosquitoes are known for transmitting vector-borne diseases like malaria, dengue fever, and West Nile virus. Their life cycles and behaviors facilitate the transmission process, making them significant in public health contexts.

The other groups mentioned do not primarily fall under the typical definition of vectors. For example, while ants and bees may have interactions that could influence disease dynamics, they are not the primary vectors for significant human diseases in the same manner as rodents and mosquitoes. Similarly, cats and dogs may carry diseases but are usually classified as hosts rather than vectors in the context of disease transmission. Frogs and fish generally do not serve as vectors for human disease transmission, as they are largely removed from the roles that vectors play in health-related contexts.