Which statement calls into question the hypothesis that there are two distinct subtypes of SSD, phonetic disorders versus phonemic disorder?

Which statement calls into question the hypothesis that there are two distinct subtypes of SSD, phonetic disorders versus phonemic disorder?

• A. Some children produce a covert contrast suggesting knowledge of misarticulated phonemes that are produced as homonyms, e.g., "can" → [tæn] and "tan" → [tæn].
• B. Some children produce phonological processes when they are younger that resolve, leaving only distortion errors when they are school-age.
• C. Some children with SSDs have difficulties with speech perception whereas others perceive speech in an adultlike manner.
• D. Some children with distortion errors do not know how to produce the articulatory gestures required for accurate production of their error sounds.

Answer: (A)

The main idea here is that speech‑sound disorders may not fit neatly into two separate, non‑overlapping subtypes. When a child’s surface speech collapses two different target phonemes into the same spoken form, but there is evidence that the child still knows there should be a contrast between those phonemes, that’s a covert contrast. It shows phonemic knowledge can exist even if the motor system can’t realize the distinction cleanly. In the example, “can” and “tan” would be produced as the same sound, yet the child’s productions reveal some awareness of a difference between the underlying phonemes. This kind of finding challenges the idea that there are two strictly separate categories—phonetic (articulatory distortion) and phonemic (phonological) disorders—because it demonstrates that phoneme knowledge and motor execution can be dissociated within the same child. The other options don’t directly push against that clean two‑subtype view. Developmental shifts from phonological processes to distortions don’t by themselves show that phonemic representations disappear or that two pure subtypes are required. Variation in speech perception among children reveals heterogeneity but doesn’t address whether surface distortions always map to motor versus phonological causes. And when distortion errors are tied to a lack of knowledge about articulatory gestures, that aligns with a motor‑based explanation rather than undermining the idea of two subtypes.

The main idea here is that speech‑sound disorders may not fit neatly into two separate, non‑overlapping subtypes. When a child’s surface speech collapses two different target phonemes into the same spoken form, but there is evidence that the child still knows there should be a contrast between those phonemes, that’s a covert contrast. It shows phonemic knowledge can exist even if the motor system can’t realize the distinction cleanly. In the example, “can” and “tan” would be produced as the same sound, yet the child’s productions reveal some awareness of a difference between the underlying phonemes. This kind of finding challenges the idea that there are two strictly separate categories—phonetic (articulatory distortion) and phonemic (phonological) disorders—because it demonstrates that phoneme knowledge and motor execution can be dissociated within the same child.

The other options don’t directly push against that clean two‑subtype view. Developmental shifts from phonological processes to distortions don’t by themselves show that phonemic representations disappear or that two pure subtypes are required. Variation in speech perception among children reveals heterogeneity but doesn’t address whether surface distortions always map to motor versus phonological causes. And when distortion errors are tied to a lack of knowledge about articulatory gestures, that aligns with a motor‑based explanation rather than undermining the idea of two subtypes.