Answer:
b. red algae—eukaryotes that acquired plastids by secondary endosymbiosis
Step-by-step explanation:
- Red algae did not acquire plastids by secondary endosymbiosis and thus, option b is an incorrect pair.
- Red algae are eukaryotes that are red in the color not because they acquired plastids y endosymbiosis but because they produce the enzyme phycoerythrin and phycocyanin which masks the other pigments present in it.
- Secondary endosymbiosis is a process by which the product of primary endosymbiosis is engulfed by another organism. Such type of process never occurred in case of red algae.