On some areas of the seafloor, one could observe an "ooze" that is hundreds of meters thick. What creates this ooze?

• A. The tests of dead diatoms
• B. The decaying porous shells of forams
• C. The gel-forming polysaccharides secreted by brown and red algae
• D. Colonies of plasmodial slime molds
• E. The tests of dead radiolarians

Answer: (E)

Verified step by step guidance

1. Begin by understanding what 'ooze' refers to in the context of the seafloor. Ooze is a type of sediment found on the ocean floor, primarily composed of the remains of microscopic organisms.
2. Identify the types of organisms that contribute to the formation of ooze. These include radiolarians, diatoms, and foraminifera, which are all types of plankton with silica or calcium carbonate shells.
3. Focus on radiolarians, which are protozoa with intricate silica skeletons. When they die, their silica tests (shells) accumulate on the seafloor, contributing to the formation of siliceous ooze.
4. Differentiate between siliceous ooze and calcareous ooze. Siliceous ooze is formed from the silica-based tests of organisms like radiolarians and diatoms, while calcareous ooze is formed from calcium carbonate shells of foraminifera and coccolithophores.
5. Conclude that the 'ooze' observed on the seafloor in this context is primarily created by the accumulation of the tests of dead radiolarians, which are silica-based and contribute to siliceous ooze.