Which plant has features such as spiny fruits and inconspicuous green flowers?

The correct choice is Spur Weed, known scientifically as Eryngium species. This plant is characterized by its distinctive spiny fruits that can be quite formidable if one attempts to handle them. The inconspicuous green flowers of Spur Weed often go unnoticed, as they lack the vibrant colors that many other flowering plants display.

Spur Weed's growth habit and adaptations contribute to its resilience and ability to thrive in various environments, particularly in disturbed areas or road sides. The plant’s spiny attributes serve a purpose beyond mere aesthetics; they can deter herbivores from feeding on it, providing a survival advantage.

In contrast to the other plants listed, Black Medic, Cudweed, and Dandelion have different morphological characteristics that do not align with the description provided. Black Medic features yellow flowers and clovers-like leaves; Cudweed tends to have white, fuzzy flowers; and Dandelion is well-known for its bright yellow flower heads and fluffy seed heads, making them quite dissimilar to the characteristics of Spur Weed. Understanding these distinctions solidifies why Spur Weed is the plant being described.