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The following paragraph is a close test. Please check out if my answers in boldface are acceptable. Thanks!

The task of ___(1)____ language is one for which the adult has lost most of her aptitude but one the child will perform with remarkable skill. Within a short span of time and with almost no direct ____(2)___ the child will analyze the language completely. In fact, although many subtle refinements are added between the ages of five and ten, most children have completed the greater part of the basic language-acquisition process by the age of five. By that time a child will have ___(3)____ the language into its minimal separable units of sound and meaning; she will have discovered the rules for recombining words into meaningful sentences, and she will have ____(4)____ the intricate patterns of taking turns in dialogue. All in all she will have established herself linguistically as a ____(5)___ member of a social community, informed about the most subtle details of her native language as it is spoken in a wide variety of situations.

1. (A) studying (B) acquiring (C) conferring (D) investigating
2. (A) construction (B) prescription (C) instruction (D) induction
3. (A) arranged (B) diagnosed (C) dissected (D) investigated
4. (A) analyzed (B) internalized (C) translated (D) induced
5. (A) full-fledged (B) incompetent (C) distinguished (D) obscene