Which of the following groups of organisms have kidneys as their excretory organs ?

Options

A. Tunicates, Lancelets Cyclostomes , chondrichthyes, Osteichthyes and Amphibians
B. Cyclostomes , chondrichthyes, Osteichthyes and Amphibians
C. Lancelets Cyclostomes , chondrichthyes, Osteichthyes and Amphibians
D. Tunicatse Cyclostomes , chondrichthyes, Osteichthyes and Amphibians

Answer

To determine which group of organisms has kidneys as their excretory organs, we will analyze each option provided in the question.

### Step 1: Analyze the first option
- **Option 1**: Tunicates, Lenslates, Cyclostome, Chondrichthyes, Osteichthyes, and Amphibians.
- **Tunicates**: They have a simple excretory system and do not possess kidneys.
- **Lenslates**: They have paired nephritia but not true kidneys.
- **Cyclostomes**: They have a primitive excretory system.
- **Chondrichthyes (cartilaginous fish)**: They have kidneys.
- **Osteichthyes (bony fish)**: They also have kidneys.
- **Amphibians**: They have well-developed kidneys.

Since Tunicates and Lenslates do not have kidneys, this option is incorrect.

### Step 2: Analyze the second option
- **Option 2**: Cyclostomes, Chondrichthyes, Osteichthyes, and Amphibians.
- **Cyclostomes**: As mentioned, they have a primitive excretory system.
- **Chondrichthyes**: They possess kidneys.
- **Osteichthyes**: They possess kidneys.
- **Amphibians**: They possess kidneys.

Although Cyclostomes do not have kidneys, the presence of kidneys in Chondrichthyes, Osteichthyes, and Amphibians makes this option correct.

### Step 3: Analyze the third option
- **Option 3**: Lenslate, Cyclostome, Chondrichthyes, Osteichthyes, and Amphibians.
- **Lenslates**: As previously stated, they do not have true kidneys.
- **Cyclostomes**: They have a primitive excretory system.
- **Chondrichthyes**: They have kidneys.
- **Osteichthyes**: They have kidneys.
- **Amphibians**: They have kidneys.

Since Lenslates and Cyclostomes do not have kidneys, this option is incorrect.

### Step 4: Analyze the fourth option
- **Option 4**: Tunicates, Cyclostome, Chondrichthyes, Osteichthyes, and Amphibians.
- **Tunicates**: They do not have kidneys.
- **Cyclostomes**: They have a primitive excretory system.
- **Chondrichthyes**: They have kidneys.
- **Osteichthyes**: They have kidneys.
- **Amphibians**: They have kidneys.

Since Tunicates and Cyclostomes do not have kidneys, this option is also incorrect.

### Conclusion
The correct answer is **Option 2: Cyclostomes, Chondrichthyes, Osteichthyes, and Amphibians**. While Cyclostomes do not have kidneys, the other groups do, making this option the best choice.