In a play environment, what is considered the most interesting object for newborns and very young infants?

The most interesting object for newborns and very young infants is a live human face. Infants are naturally drawn to faces due to their instinctual preference for social stimuli. Human faces provide emotional cues, expressions, and social interactions that are crucial for a newborn's development. Babies are visually attuned to faces even at a very young age, showing preferences for symmetrical, high-contrast features typical of human faces. This natural attraction helps them form attachments and encourages bonding with caregivers. In contrast, while brightly colored toys, mirrors, and plush stuffed animals can capture an infant's attention as well, they do not offer the same social interaction and emotional engagement that a human face does.