Which cognitive milestone is observed at 13-15 months?

• A. Uses 2 related objects
• B. Uses object to perform social action
• C. Matches objects
• D. Pays attention longer

Answer: (A)

At 13–15 months, children begin using two related objects together in a single action, showing emerging functional play and problem-solving. This means they understand that objects can work in tandem within a familiar activity. For example, they might use a cup and spoon in a feeding-themed action or place and remove a lid as part of a pretend task. This coordinated use of two items reflects planning and goal-directed behavior with objects, a milestone commonly seen in this age range.

The other options describe different skills that don’t align as reliably with this specific age window. Using an object to perform a social action relates more to social-communication gestures and imitation and isn’t the hallmark milestone at this age. Matching objects is a separate cognitive task that develops variably and often appears a bit later or with more experience. Paying attention longer is a general maturation trend, not a discrete milestone tied to this exact period.