<span>I believe the answer is C. Grasslands and forests do not have permafrost--present in tundra and taiga so A can be eliminated. B is not right because forests and grasslands definitely do not get TOO much rain, assuming they're not talking about tropical rain forests. </span>
Answer: a. decreases the present and future risk to human properties
Explanation:
Properties along the coasts can be in danger when high tides come in. This can however be mitigated by walls protecting those properties as it would take a significantly high tide (flood proportion) to scale those walls and come in and damage the property.
These walls therefore not only decrease the present risk to human properties but if maintained, decrease the future risks as well.