From the early Vedic Period to the late Vedic Period, the most accurate conclusion regarding the change in gender structures in early India is that:
Women gained higher status as they gained greater responsibilities in performing religious rituals.
During the early Vedic Period, women enjoyed a relatively high status and had the freedom to participate in various aspects of society, including education and religious practices. However, by the late Vedic Period, although women did face some restrictions, particularly related to social norms and roles, they also began to take on more responsibilities in specific religious contexts, which indicates a complex evolving status rather than a straightforward decline.
The other options—suggesting women lost all rights, were socially isolated but retained property rights or simply could marry post-puberty—do not fully encapsulate the nuanced changes in the societal roles and rights of women during this transition in early Indian history.