Answer:
Glucose
Explanation:
Photosynthesis is the process in which light energy is converted to chemical energy in the form of sugars. In a process driven by light energy, glucose molecules (or other sugars) are constructed from water and carbon dioxide, and oxygen is released as a byproduct.
Spicules are structural elements found in most sponges. They provide structural support and deter predators. Large spicules that are visible to the naked eye are referred to as megascleres, while smaller, microscopic ones are termed microscleres.
The answer is b. This can be remembered if you know that photosynthesis creates oxygen. Just remember that 'phytoplankton' starts with 'ph' just like 'photosynthesis', and you'll know that phytoplakton also create oxygen.
Salt water is denser than cold water because fresh water sinks when it is in salt water.