The marine multicellular protists including the larger brown algae belong to the

Options for the question have not been given. They are as follows:

A. dinoflagellates.

B. Choanoflagellida.

C. Stramenopiles.

D. euglenoids.

E. foraminifera.

C. Stramenopiles

Explanation:

Stramenopiles or heterokonts are a part of Chromista kingdom. They comprise of both unicellular and multicellular protists. They are characterized by presence of two dissimilar flagella in the motile life cycle stage. Their chloroplast is also surrounded by four membranes which indicates origin from symbiotic relationship. They include many classes like diatoms, golden algae and brown algae. Brown algae belongs to the class Phaeophyceae. They are marine multicellular algae and are commonly known as seaweeds.