Answer:
The correct answer would be A. cell walls; plant-like
Diatoms are unicellular algae which belong to kingdom Protista.
Their cell walls are made up of organic material and silica.
The silica obtained from diatom has abrasive properties which help in polishing the materials which are soft and easy to damage.
Due to this reason, diatoms are used in toothpaste and tooth powder and are occasionally used in bath products such as soaps.
The part and type of protist that is part of toothpaste is the cell wall and plant-like protists.
The plant-like protists are the algae.
The group of algae whose cell walls are utilized in the manufacturing of toothpaste is known as diatoms.
When diatoms die, their remains form diatomites which can be ground into powder and used as toothpaste additives, among other uses.
More on diatoms can be found here: https://brainly.com/question/2507344
