Human races may be Dolichocephalic , when index is
**Core Concept**
The human skull shape is classified based on the cranial index, which is the ratio of the maximum width of the skull to its maximum length. Dolichocephalic skulls have a longer length compared to their width, resulting in a more elongated shape.
**Why the Correct Answer is Right**
A dolichocephalic skull has a cranial index of 75 or less, indicating a relatively longer skull length compared to its width. This is in contrast to brachycephalic skulls, which are shorter and wider. The cranial index is an important anthropometric measurement used in forensic anthropology and physical anthropology to classify human skulls into different shapes and sizes.
**Why Each Wrong Option is Incorrect**
* **Option B:** This option is incorrect as it does not specify the correct range for dolichocephalic skulls. The correct range is 75 or less.
* **Option C:** This option is incorrect as it does not specify the correct index value. The correct index value for dolichocephalic skulls is 75 or less.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the cranial index is a continuous variable and can vary across different populations and individuals. Therefore, it's not always possible to categorize a skull as strictly dolichocephalic or brachycephalic based on a single measurement.
**Correct Answer:** D.