A toxin or other foreign substance which induces an immune response in the body, especially the production of antibodies.
The correct option would be c.
D. Photosynthesis only takes place in the light, while cellular respiration takes place in the light and dark.
The ribosome, since all organisms need to synthesize proteins.
Coccus-shaped bacteria can be found in pairs, chains, squares of four, cubes of eight, or grape like clusters. More specificially, this type of bacteria found in pairs is called diplococcia, in chains is called streptococci, in squares of four is called tetrads, in cubes of eight is called sarcinae, and in grape like clusters called staphylocci.