Concept:Water-dispersed fruits must float and protect their seeds.
Explanation:Fruits carried by water usually develop a fibrous covering or husk.
This fibrous outer layer traps air inside the fruit.
Trapped air lowers the overall density of the fruit.
As a result, the fruit becomes buoyant and can float easily on water.
The fibrous covering also helps keep water out, protecting the seed from rotting.
A smooth surface does not ensure floating or water resistance.
High water content makes a fruit heavier and less likely to float.
The pericarp is the general fruit wall and not a special water-dispersal adaptation.
Answer:A. fibrous covering