题目选项分析

Microscopic plants called algae grow inside the top layer of sea ice in the Antarctic if enough sunlight reaches that layer of ice and enough seawater, which contains nutrients, reaches that layer after splashing onto the surface. Even though moderate snow cover reduces the sunlight that filters into the top layer, sea ice with moderate snow cover typically contains even more algae in the top layer than does sea ice with less snow cover.

Which of the following, if true, most helps to explain the apparent discrepancy?

【选项】Seawater in the Antarctic often contains higher concentrations of nutrients than does seawater in more temperate regions.