In some species, individuals forego reproduction and help bring up another individuals offspring. Such altruistic behaviour CANNOT be explained by which of the following?

Options

A. An individual helps relatives only and gets indirect genetic benefits.
B. The individual benefits because it can later inherit the breeding position.
C. The individual benefits because it gets access to resources, such as food and security from predators, in return.
D. The species benefits from a reduction in competition among offspring.

Answer

To solve the question regarding altruistic behavior in some species where individuals forego reproduction to help raise another individual's offspring, we need to analyze the options provided and determine which explanation does not fit the concept of altruism.

### Step-by-Step Solution:

1. **Understanding Altruistic Behavior**: Altruism in biology refers to behavior by an individual that increases the fitness of another individual while decreasing the fitness of the actor. This is often seen in social animals where individuals may help raise the offspring of others.

2. **Analyzing the Options**:
- **Option A**: "An individual helps relatives only and gets indirect genetic benefits."
- This option aligns with kin selection, where helping relatives can increase the likelihood of shared genes being passed on. This is a valid explanation for altruistic behavior.

- **Option B**: "The individual benefits because it can later inherit the breeding position."
- This option suggests a direct benefit to the individual helping, which contradicts the concept of altruism, as altruism involves sacrificing one's own reproductive success for others. This option is likely the correct answer.

- **Option C**: "The individual benefits because it gets access to resources such as food and security from predators in return."
- This option indicates a reciprocal relationship where the helper gains benefits in return for their assistance. While this is a form of cooperation, it does not strictly fit the definition of altruism, but it does not negate the possibility of altruistic behavior either.

- **Option D**: "The species benefits from the reduction in competition among offspring."
- This option suggests that by helping raise others' offspring, competition is reduced, which can be beneficial for the species as a whole. This can also be seen as a valid explanation for altruistic behavior.

3. **Conclusion**: After analyzing the options, it is clear that **Option B** is the one that cannot explain altruistic behavior, as it implies a direct benefit to the individual helping, which contradicts the essence of altruism.

### Final Answer:
**Option B**: "The individual benefits because it can later inherit the breeding position."