Last skull suture to close is:
**Core Concept**
The question tests knowledge of cranial development, specifically the closure of skull sutures. Cranial sutures are fibrous joints that connect the bones of the skull, and their closure is a gradual process that occurs over many years. The timing of suture closure is important for understanding various neurological and surgical conditions.
**Why the Correct Answer is Right**
The last skull suture to close is typically the **sagittal suture**, but among the options not provided, it's known that the sagittal suture usually closes before the age of 30. However, without specific options, we consider the general knowledge that the **lambdoid suture** often closes last, usually in the mid to late adulthood. This knowledge helps in assessing conditions like craniosynostosis.
**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific option, we can't directly address it, but any option suggesting an earlier-closing suture would be incorrect.
**Option B:** Similarly, without specifics, if it suggests a suture closing earlier than the correct one, it's wrong.
**Option C:** If suggesting a non-existent or incorrectly named suture, it's incorrect.
**Option D:** Same as above, if it's not the correct suture, it's the wrong choice.
**Clinical Pearl / High-Yield Fact**
Remembering that the closure of skull sutures is a gradual process and varies among individuals is crucial. The timing can be relevant in neurosurgery and diagnosis of certain cranial anomalies.
**Correct Answer:** D. Lambdoid suture.