Backward is to forward as ancestry is to what?

The relationship between "backward" and "forward" is one of opposites or directional contrasts. Similarly, "ancestry" refers to a person's lineage or heritage, while "progeny" denotes descendants or offspring. This opposition highlights the contrast between the past (ancestry) and the future (progeny).

Choosing "progeny" complements the relationship established by the original pair, reflecting the movement from earlier generations to those that follow. Ancestry pertains to one’s roots in the past, while progeny points to what comes next. This parallel structure reinforces the correct answer. In contrast, while "origin" and "lineage" are related to ancestry, they do not encapsulate the same forward-reverse dynamic, and "prototype" typically refers to an initial model rather than a descendant relationship. Thus, "progeny" is the best fit for this analogy.