\begin{equation}
\begin{array}{l}{\text { When climbing a mountain, we can observe transitions in }} \\ {\text { biological communities that are analogous to the changes }} \\ {\text { (A) in biomes at different latitudes. }} \\ {\text { (B) in different depths in the ocean. }} \\ {\text { (C) in a community through different seasons. }} \\ {\text { (D) in an ecosystem as it evolves over time. }}\end{array}
\end{equation}