Which is an example of offset ?
(a) Cynodon dactylon
(b) Eichhornia
(c) Fragaria
(d) Mentha

Options

A. Cynodon dactylon
B. Eichhornia
C. Fragaria
D. Mentha

Answer

To solve the question "Which is an example of offset?" we need to analyze the given options and understand what an offset is.

### Step-by-Step Solution:

1. **Understand the term 'offset':**
- An offset is a type of vegetative structure that helps in the asexual reproduction of plants. It is a small lateral shoot that develops from the base of the parent plant and can grow into a new individual.

2. **Analyze the options:**
- **(a) Cynodon dactylon:**
- Commonly known as Bermuda grass or Doob grass. This plant does not reproduce via offsets; instead, it spreads through rhizomes and stolons. Therefore, this is **not an example of offset**.

- **(b) Eichhornia:**
- Known as water hyacinth, Eichhornia reproduces through offsets. It produces a floating rosette of leaves and forms new plants from the offsets. Thus, this is **an example of offset**.

- **(c) Fragaria:**
- This is the genus for strawberries. Strawberries reproduce through runners (stolons) rather than offsets. Hence, this is **not an example of offset**.

- **(d) Mentha:**
- Commonly known as mint, this plant also reproduces through runners rather than offsets. Therefore, this is **not an example of offset**.

3. **Conclusion:**
- After analyzing all the options, the only plant that is an example of offset is **Eichhornia**.

### Final Answer:
**(b) Eichhornia**