[A]: Generally the intraspecific competition is more intense than interspecific competition.
[R]: lntraspecific competition occurs when the resources are in short supply.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

To analyze the assertion and reason provided in the question, we will break down the concepts of intraspecific and interspecific competition step by step.

### Step 1: Understanding Intraspecific Competition
- **Definition**: Intraspecific competition occurs when individuals of the same species compete for limited resources such as food, space, and mates.
- **Example**: A group of deer competing for the same food source in a forest.

### Step 2: Understanding Interspecific Competition
- **Definition**: Interspecific competition occurs when individuals of different species compete for similar resources.
- **Example**: Different species of birds competing for nesting sites in the same tree.

### Step 3: Comparing Intensity of Competition
- **Intraspecific Competition**: Generally more intense because individuals of the same species have identical needs and requirements. They compete directly for the same resources.
- **Interspecific Competition**: Less intense because different species may have different resource requirements. They may compete for some resources, but not all needs overlap.

### Step 4: Analyzing the Assertion
- **Assertion**: "Generally, intraspecific competition is more intense than interspecific competition."
- **Evaluation**: This statement is true because the competition for identical resources among the same species leads to greater intensity.

### Step 5: Analyzing the Reason
- **Reason**: "Intraspecific competition occurs when the resources are in short supply."
- **Evaluation**: This statement is also true. Intraspecific competition often arises when resources are limited, leading individuals to compete more fiercely.

### Step 6: Relationship Between Assertion and Reason
- **Connection**: While both statements are true, the reason does not adequately explain why intraspecific competition is more intense than interspecific competition. The intensity is primarily due to the identical needs of the same species rather than simply the short supply of resources.

### Conclusion
- **Final Evaluation**: Both the assertion and reason are true, but the reason is not the correct explanation for the assertion. Therefore, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation.

### Answer:
Both assertion and reason are true, but the reason is not the correct explanation for the assertion.

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