**Core Concept:**
Audiometry is a test used to measure a person's hearing thresholds at various frequencies. Infants are particularly sensitive to sound, and their auditory abilities develop rapidly during the first few months of life. The purpose of audiometric screening in infants is to identify hearing loss early, enabling timely intervention and therapy.

**Why the Correct Answer is Right:**
The correct answer is **D** - the most sensitive audiometric screening in infants is using air conduction and bone conduction. This method measures the child's response to sounds presented through a soft plastic earphone and a bone vibrator. By comparing the two responses, any difference can indicate a potential hearing impairment.

**Why Each Wrong Option is Incorrect:**
A) **B:** Otoacoustic emissions (OAEs) are a less sensitive method for infants due to their immature auditory system and immature cochlea function.
B) **C:** Pure-tone audiometry is less sensitive for infants because it measures only the ability to recognize sounds, not the threshold of hearing.
C) **A:** Middle ear function is crucial in interpreting auditory brain stem response (ABR) results, which may be abnormal in infants with conductive hearing loss.

**Why Different Options are Right:**
A) **B:** Otoacoustic emissions (OAEs) are more suitable for infants later in development, such as in toddlers and preschoolers, when the auditory system matures.
C) **A:** Auditory brainstem response (ABR) is a useful screening tool for infants with intact middle ear function, which is essential for accurate interpretation of ABR results.
D) **D:** Air conduction and bone conduction testing, as in option D, are more sensitive for infants due to their immature cochlea function and immature brainstem function.

**Clinical Pearl:**
Using a combination of air conduction and bone conduction testing (option D) provides a more comprehensive assessment of infants' hearing capabilities, ensuring better detection of hearing impairments and enabling timely intervention.