**Core Concept**
The question is testing the understanding of the innervation of muscles and the role of root values in motor control. The root values of a nerve refer to the specific spinal nerve roots that contribute to the formation of the nerve. In this context, the question is asking about the root values needed for the latter part of a specific muscle action.

**Why the Correct Answer is Right**
The correct answer is related to the innervation of the **tibialis anterior muscle**, which is responsible for dorsiflexion and inversion of the foot. The **tibialis anterior muscle** is primarily innervated by the **L4-S1 nerve roots**, but the **latter part of its action** requires additional innervation from the **S1 nerve root**. This is because the S1 nerve root provides the necessary motor control for the final stages of dorsiflexion and inversion.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify the correct root values needed for the latter part of the muscle action.
**Option B:** This option is incorrect because it does not accurately describe the root values required for the tibialis anterior muscle's innervation.
**Option C:** This option is incorrect because it is not relevant to the innervation of the tibialis anterior muscle.

**Clinical Pearl / High-Yield Fact**
To remember the root values for the tibialis anterior muscle, use the mnemonic "L4-S1" for the primary innervation, and add "S1" for the latter part of its action.

**Correct Answer:** C.