Final answer:
A helpful genetic mutation is best described as one that increases an organism's chances of survival, known as a beneficial mutation. These mutations lead to adaptations that can become more prevalent in the population over time. Therefore, the correct option is b.
Step-by-step explanation:
The best description of a helpful genetic mutation is one that increases an organism's chances of survival. This kind of mutation is referred to as a beneficial mutation, which generally leads to new versions of proteins that help organisms adapt to their environment. When these mutations enhance an organism's fitness — its ability to survive and reproduce — they tend to become more common in the population over time. For example, the 32 base pair deletion in human CCR5 (CCR5-Δ32) confers resistance to HIV and has become more prevalent in certain populations.