Which of the following is a developmental milestone for a 1-year-old?

The achievement of walking and saying a few words at around one year old is a significant developmental milestone. At this age, children typically begin to demonstrate their ability to walk independently, which shows important progress in their motor skills and balance. Alongside this, they also start to develop basic language skills, often saying simple words such as "mama" or "dada." Both walking and early verbal communication are crucial aspects of physical and cognitive development, indicating that the child is growing in their ability to interact with their environment and express themselves.

In contrast, reading simple words is generally a skill that develops later, typically around the preschool years when a child is more exposed to literacy activities. Riding a tricycle usually happens around the age of 3 or 4, when a child has more advanced coordination and balance. Solving puzzles also tends to emerge later as intellectual and problem-solving abilities become more developed, often seen in toddlers and preschoolers.