In the general sequence of a child's language acquisition, which of the following represents the second stage after listening/comprehension?

Between 12 to 18 months of age, children begin to produce a variety of recognizable single-unit utterances. This period, in which single terms are uttered for everyday objects, is called the:

Read the following statements: Assertion (A): Delaying the learning of languages in the early years makes it more difficult for children to acquire new languages. Reason (R): Early years of the child are sensitive periods for language acquisition. Choose the correct option.