A common characteristic feature of plant sieve tube cells and most of mammalian erythrocytes is :

Options

A. absence of mitochondria
B. presence of haemoglobin
C. presence of cell wall
D. absence of nucleus

Explanation

To determine the common characteristic feature of plant sieve tube cells and most mammalian erythrocytes, we can analyze the options provided:

1. **Absence of Mitochondria**:
- Plant sieve tube cells do contain mitochondria, while mammalian erythrocytes (red blood cells) do not. Therefore, this option is not correct.

2. **Presence of Hemoglobin**:
- Hemoglobin is present in mammalian erythrocytes, which is responsible for oxygen transport. However, it is absent in plant sieve tube cells. Thus, this option is also incorrect.

3. **Presence of Cell Wall**:
- Plant sieve tube cells have a cell wall, which is a characteristic feature of plant cells. However, mammalian erythrocytes do not have a cell wall as they are animal cells. Therefore, this option is not correct.

4. **Absence of Nucleus**:
- Both plant sieve tube cells and mammalian erythrocytes lose their nuclei at maturity. This is a key feature that allows them to perform their functions more efficiently. In the case of erythrocytes, losing the nucleus increases surface area for oxygen transport, while in sieve tube cells, it facilitates the flow of nutrients.

Based on the analysis, the common characteristic feature of plant sieve tube cells and most mammalian erythrocytes is the **absence of nucleus**.

### Final Answer:
The common characteristic feature of plant sieve tube cells and most mammalian erythrocytes is the **absence of nucleus**.