**Injury to the medial meniscus is rather impossible when the knee joint does not**

**Core Concept**
The medial meniscus is a cartilaginous structure in the knee joint that provides cushioning and stability. Injury to the medial meniscus often occurs due to excessive twisting or rotational forces on the knee joint.

**Why the Correct Answer is Right**
When the knee joint is fully extended, the medial meniscus is in a more central position, and the ligaments and bony structures surrounding the knee joint provide additional support and stability, making injury to the medial meniscus less likely. The medial meniscus is more susceptible to injury when the knee joint is flexed, as the meniscus is more likely to be caught between the tibia and femur, increasing the risk of meniscal tears.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because the knee joint can still be injured when it is fully extended, especially if there is a direct blow to the knee or a sudden twisting motion.
* **Option B:** This option is incorrect because the medial meniscus can still be injured when the knee joint is flexed, especially if there is a sudden twisting or rotational force applied to the knee.
* **Option C:** This option is incorrect because the medial meniscus can still be injured when the knee joint is in a neutral position, especially if there is a sudden twisting or rotational force applied to the knee.

**Clinical Pearl / High-Yield Fact**
It's essential to note that the medial meniscus is more susceptible to injury when the knee joint is flexed, especially in activities that involve sudden twisting or rotational forces, such as sports that involve fast changes of direction.

**Correct Answer: C.**