Which behavior is an indication of language development in mobile infants, aged 8 to 18 months?

The ability of mobile infants, aged 8 to 18 months, to look at picture books with interest serves as a significant indicator of language development. This behavior reflects their growing cognitive abilities and an increased understanding of the world around them. By engaging with picture books, infants are not just captivated by images; they are also beginning to associate words with objects and concepts. This interaction lays a foundation for language acquisition as they start to recognize that pictures represent real things and that spoken language can describe those things.

Additionally, this interest in picture books often leads to verbal expressions and interactions with caregivers, contributing further to their vocabulary and language skills. Such engagement fosters a love for reading, which is crucial for future literacy development. While the other behaviors mentioned in the choices may also relate to general developmental milestones, looking at picture books specifically emphasizes the connection between visual representation and language comprehension, making it a strong indication of language development at this stage.