The Next Few Questions Refer to the Following Description and Table

The next few questions refer to the following description and Table 28.1.
Diatoms are encased in Petri-platelike cases (valves) made of translucent hydrated silica whose thickness can be varied. The material used to store excess calories can also be varied. At certain times, diatoms store excess calories in the form of the liquid polysaccharide, laminarin, and at other times as oil. The following are data concerning the density (specific gravity) of various components of diatoms, and of their environment.
Table 28.1 Specific Gravities of Materials Relevant to Diatoms

-Judging from Table 28.1 and given that water's density and, consequently, its buoyancy decrease at warmer temperatures, in which environment should diatoms (and other suspended particles) sink most slowly?

A) cold fresh water
B) warm fresh water
C) cold seawater
D) warm seawater
E) warm brackish water