The outer boundary of cytoplasm is the answer
The correct option is "D", "<span>The density of seawater".
As you are measuring the</span><span> amount of mass in a volume of water and if we look at the definition of density, it is the mass per unit volume.
D = m/v
where m is the mass of an object and v is the volume.
Thus, d is the correct option.</span>
Not a lot of people have creativity so the ppl that do are creative i guess couldn't think of another word