The term protista refers to :
a) a kingdom within the superkingdom sar.
b) a kingdom within the superkingdom excavata.
c) it is a descriptive term or common name for unicellular, colonial, and some multicellular organisms that lack true tissues.
d) a phylum within the kingdom metazoa.

The correct answer will be option C.

Explanation:

Protista is a group of Eukaryotic organisms which consists of unicellular organisms.  

These protists remain unicellular which live in colonies as well as some group live as a simple multicellular organism. these multicellular organisms lack complexity, unlike true multicellular organisms. Protists exhibit the characters of plants, animals and fungi but lack true tissues like seaweed kelp.

Thus, option C is the correct answer.

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