A connecting link between plant and animal kingdom is
Paramecium
Chlamydomonas
Chlorella
Euglena
D.
Euglena
Euglena can be considered as both plants as well as an animal. It can perform photosynthesis in presence of light. But in the absence of light, it opts holozoic mode nutrition which is the feature of animals. Thus, Euglena is considered as connecting link between plant and animal kingdom.