What is the most common and primitive type of ovule, respectively?
(a) circinotropous and campylotropous ovule
(b) Amphitrophous and orthotropous ovule
(c) Orthotropous and anatropous ovule
(d) Anatropous and orthotropous ovule

Options

A. circinotropous and campylotropous ovule
B. Amphitrophous and orthotropous ovule
C. Orthotropous and anatropous ovule
D. Anatropous and orthotropous ovule

Answer

To solve the question about the most common and primitive type of ovule, we will analyze each option provided and identify the correct answer step by step.

### Step 1: Understand the Types of Ovules
We need to know the definitions and characteristics of the different types of ovules mentioned in the options.

1. **Circinotropous Ovule**: This type has a long funicle that forms a complete circle around the ovule. It is not the most common type.

2. **Campylotropous Ovule**: In this type, the ovule is curved, and the micropyle is directed towards the chalaza. It is also not considered primitive or common.

3. **Amphitrophous Ovule**: Known as the transverse ovule, it has a prominent curvature but is not the most common type.

4. **Orthotropous Ovule**: This is the simplest and most primitive type of ovule, where the micropyle, chalaza, and funicle are in a straight line.

5. **Anatropous Ovule**: This is known as the inverted ovule and is the most common type of ovule, found in about 80% of angiosperms.

### Step 2: Analyze Each Option
Now, let's analyze each option based on the definitions:

- **Option (a)**: Circinotropous and Campylotropous ovule
- Not the most common or primitive.

- **Option (b)**: Amphitrophous and Orthotropous ovule
- Orthotropous is primitive, but Amphitrophous is not common.

- **Option (c)**: Orthotropous and Anatropous ovule
- Orthotropous is primitive, and Anatropous is common. This could be a potential answer.

- **Option (d)**: Anatropous and Orthotropous ovule
- Anatropous is common, but Orthotropous is primitive. This is also a potential answer.

### Step 3: Identify the Correct Pair
From the analysis:
- The **most common type of ovule** is **Anatropous**.
- The **most primitive type of ovule** is **Orthotropous**.

Thus, the correct answer is **(c) Orthotropous and Anatropous ovule**.

### Final Answer
The most common and primitive type of ovule, respectively, is **(c) Orthotropous and Anatropous ovule**.