Final answer:
A G-ratio of 1.0 corresponds to a complete lack of myelination.
Step-by-step explanation:
In the context of myelination, the G-ratio refers to the ratio between the inner axon diameter and the diameter of the myelinated sheath surrounding it. A G-ratio of 1.0 is considered normal, indicating a balance between the axon and the myelin sheath.
A complete lack of myelination would mean that there is no myelin sheath present around the axon. This would result in a larger axon diameter relative to the absence of myelin, leading to a higher G-ratio. Therefore, the value of the G-ratio that would correspond to a complete lack of myelination is option B: 1.0.