Final answer:
Given the bilingual environment of the 12-month-old boy who has not started saying 'mama' or 'dada' yet, the initial priority intervention is to perform a developmental evaluation. This should help identify whether the child is merely experiencing typical variance in developmental timelines or whether there may be a case of language acquisition delay. Further steps can be determined following this initial evaluation.
Step-by-step explanation:
The priority intervention for a 12-month-old boy not yet saying 'mama' or 'dada', given his bilingual environment, would be A) Performing a developmental evaluation of the child. This early evaluation is essential for detecting if there is a delay in the child's language acquisition or if it is just the typical variation in the timeline of such developmental milestones.
Before one year of age, children start to produce sounds related to their surrounding language (babbling stage). By about 12 months, the first word with meaning tends to appear. The presence of different languages in the environment can offer a larger phonemes palette, and the baby discriminates these phonemes, even if he or she doesn't utter recognizable words. The child is likely imitating the tones and rhythms of both English and Spanish.
Therefore, developmental evaluation is necessary. It's crucial to remember that children learn via exposure and interaction, regardless of the number of languages in the environment. If after this evaluation there appears to be a delay, then referring the child to a developmental specialist would be the next step.
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