**Grid Placement**

**Core Concept**
When an X-ray is taken, a grid is placed between the patient and the X-ray detector to reduce scatter radiation and improve image quality. This is particularly useful in patients with high soft tissue density, such as the chest or abdomen.

**Why the Correct Answer is Right**
The grid consists of a series of parallel lead strips that absorb scatter radiation while allowing the primary X-ray beam to pass through. This results in a reduction of noise in the image and an improvement in contrast. The grid is typically placed between the patient and the detector, as this is where the scatter radiation is most intense.

**Why Each Wrong Option is Incorrect**
* **Option A:** Incorrect, as the grid is not placed between the patient and the X-ray source.
* **Option B:** Incorrect, as the grid is not placed on the patient's skin.
* **Option C:** Incorrect, as the grid is not placed on the X-ray detector.

**Clinical Pearl / High-Yield Fact**
When using a grid, it's essential to adjust the grid ratio to match the patient's thickness. A grid ratio that is too high may result in a loss of detail, while a ratio that is too low may not provide sufficient scatter reduction.

**Correct Answer: C. The grid is placed between the patient and the X-ray detector.**