Identify a suborder of Mollisols.

Mollisols are a soil order characterized by their rich organic matter content, dark color, and good fertility, typically found in grassland regions. This order is further divided into suborders based on moisture regimes and other characteristics.

The suborder designations for Mollisols include specific letters that indicate their properties:

• The designation "Alb" indicates the presence of an albic horizon, which is typically light-colored and indicates leaching.

• "Aq" signifies a Mollisol that has been influenced by water or has wet conditions, implying characteristics similar to those of aquic moisture regimes.

• "Ud" refers to soil that is part of a humid climate, suggesting that it has a moisture regime that supports more consistent wetness throughout the year.

Since all three choices provided, Alb, Aq, and Ud, are valid suborder classifications of Mollisols, selecting "All of the above" is indeed the correct choice. This highlights the diverse nature of Mollisols and their adaptability to various environmental conditions while maintaining their defining properties.