What anatomical feature do bed bug nymphs lack compared to adult bed bugs?

Bed bug nymphs differ from adult bed bugs primarily in their anatomical features, particularly in the development of wings. While adult bed bugs possess fully developed wings, which are non-functional for flight, nymphs are entirely wingless. This distinguishing characteristic highlights the developmental stages of bed bugs, where nymphs undergo a series of molts before reaching adulthood, during which they gradually develop the physical traits seen in adult bed bugs.

In contrast to this key distinction, nymphs and adults have similar structures in terms of legs and feeding habits; nymphs feed just as adults do, and both have multiple legs. The color pattern can vary between nymphs and adults but is not as defining as the absence of wings in nymphs. Hence, the correct answer emphasizes a notable anatomical difference that is significant in understanding the life cycle and development of bed bugs.