**Core Concept**
Sexual assault on a child can result in hymenal trauma, but in some cases, the hymen may appear intact due to various reasons. This is because the hymen is a thin membrane that can tear or stretch, but not always rupture completely.

**Why the Correct Answer is Right**
One reason the hymen may remain intact despite sexual assault is that it can be stretched or torn, but not completely severed. This is because the hymen is made of elastic tissue that can accommodate varying sizes of vaginal openings. In addition, the hymen can be partially or completely absent in some individuals, making it difficult to determine if trauma has occurred. Furthermore, the hymen can be influenced by various factors, such as age, genetics, and hygiene, which can affect its appearance and elasticity.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not provide a plausible reason for the hymen to remain intact despite trauma. While it is true that some hymens are naturally more elastic than others, this does not account for the hymen remaining intact in cases of sexual assault.

**Option B:** This option is incorrect because it is a vague term that does not provide a clear explanation for the hymen remaining intact. While it is true that some hymens can be stretched or torn, this does not account for the hymen remaining intact in cases of significant trauma.

**Option C:** This option is incorrect because it implies that the hymen is always fully intact and cannot be damaged. However, the hymen can be stretched, torn, or partially severed in cases of sexual assault.

**Option D:** This option is incorrect because it implies that the hymen is always fully intact and cannot be damaged. However, the hymen can be stretched, torn, or partially severed in cases of sexual assault.

**Clinical Pearl / High-Yield Fact**
In cases of suspected child sexual assault, it is essential to perform a thorough medical examination, including a pelvic exam, to assess for any signs of trauma, including hymenal damage. The presence or absence of hymenal trauma should not be used as the sole indicator of whether an assault has occurred.

**Correct Answer: C**. The hymen can be stretched or torn, but not always rupture completely, which can make it difficult to determine if trauma has occurred.