Organisms that breed many times during life time and produce small number of large sized offspring are.

Options

A. Pacific salmon fish
B. Mammals
C. Oysters
D. Pelagic fishes

Answer

To solve the question "Organisms that breed many times during their lifetime and produce a small number of large-sized offspring are," we can analyze the given options step by step.

### Step 1: Understand the Characteristics
We need to identify organisms that:
1. Breed multiple times during their lifetime.
2. Produce a small number of offspring.
3. The offspring are large in size.

### Step 2: Analyze the Options
Let's evaluate each option provided:

- **Pacific Salmon Fish**:
- They breed only once in their lifetime (semelparity).
- This option does not meet the criteria.

- **Mammals**:
- Mammals typically breed multiple times throughout their lives.
- They usually produce a small number of offspring (e.g., one or two at a time) and these offspring are relatively large compared to other species.
- This option meets both criteria.

- **Oysters**:
- Oysters produce a large number of eggs at once (many offspring).
- This option does not meet the criteria.

- **Pelagic Fishes**:
- Similar to oysters, pelagic fishes often release a large number of eggs at once.
- This option does not meet the criteria.

### Step 3: Conclusion
From the analysis, the only organism that meets both criteria of breeding many times and producing a small number of large-sized offspring is **Mammals**.

### Final Answer
**Mammals** are the organisms that breed many times during their lifetime and produce a small number of large-sized offspring.

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