Given below are some general characters of a chordate .
(A) skin is dry without glands, except oil gland at the base of the tail.
(B) warm-blooded (homeothermic) animal.
(C) The heart is completely four-chambered with right systemic arch.
(D) The digestive tract has additional chambers , the crop and gizzard .
Identify the animal on the basis of these characters.

Options

A. Ichthyophis
B. Crocodilus
C. Columba
D. Macropus

Answer

To identify the animal based on the given characteristics, we will analyze each character step by step.

### Step 1: Analyze the Skin Character
- The first character states that the skin is dry without glands, except for an oil gland at the base of the tail.
- This characteristic is typical of birds, as they have dry skin covered with feathers and possess a preen gland (oil gland) at the base of their tail.

**Hint:** Think about animals with feathers and dry skin.

### Step 2: Analyze the Temperature Regulation
- The second character mentions that the animal is warm-blooded (homeothermic).
- Birds are warm-blooded, meaning they can maintain a constant body temperature regardless of the environment.

**Hint:** Consider animals that can regulate their body temperature internally.

### Step 3: Analyze the Heart Structure
- The third character describes a heart that is completely four-chambered with a right systemic arch.
- Birds have a four-chambered heart, consisting of two atria and two ventricles, which allows for efficient separation of oxygenated and deoxygenated blood.

**Hint:** Recall the heart structure of birds compared to other vertebrates.

### Step 4: Analyze the Digestive System
- The fourth character states that the digestive tract has additional chambers, specifically a crop and gizzard.
- Birds possess a crop for storage of food and a gizzard for grinding food, which is a unique adaptation in their digestive system.

**Hint:** Think about animals that have specialized digestive organs for processing food.

### Conclusion
Based on the analysis of all four characteristics:
- The animal with dry skin (with oil glands), that is warm-blooded, has a four-chambered heart, and possesses a crop and gizzard is a bird.
- Among the options provided, **Columba** (the scientific name for pigeons) fits all these characteristics.

**Final Answer:** The animal is **Columba** (a bird).