Which weed is characterized by yellowish-green tubers and is considered a perennial?

The correct choice is Yellow Nutsedge. This weed is distinguished by its yellowish-green tubers, which are swelling areas on its roots that store energy and nutrients, enabling the plant to thrive even in adverse conditions. As a perennial plant, Yellow Nutsedge can survive multiple growing seasons, regrowing from its tubers each year. This resilience makes it a persistent problem for agricultural operations, as it can easily spread and outcompete other crops.

In contrast, the other options listed are annual or biennial plants with different characteristics. Pigweed, for instance, is typically an annual that completes its life cycle within one growing season and doesn't feature tubers. Hoary cress, while perennial, has a different appearance and propagation method that does not involve yellowish-green tubers. Wild carrot, also known as Queen Anne's lace, is primarily a biennial plant and does not possess the distinct tuber structure present in Yellow Nutsedge. Understanding the unique aspects of each weed, including growth habits and reproductive strategies, is crucial for effective weed management in agriculture.