Read the following statements and find out the incorrect statement.

Options

A. Plant, animals and fungi differ so greatly in external morphology, internal structure and physiology but when it comes to sexual mode of reproduction, they share a similar pattern
B. In annual and biennial plants, there is a clear cut, vegetative, reproductive and senescent phase, but in the parennial species it is very difficult to clearly define these phases
C. In animals, the juvenile phase is followed by morphological and physiological changes prior to active reproductive behaviour
D. The females of the marsupial mammals exhibit cyclical changes in the activities of ovaries and accessory ducts as well as hormones during the reproductive phase.

Answer

To solve the question of identifying the incorrect statement among the given options, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement Analysis**:
- **Statement 1**: "Plants, animals, and fungi differ greatly in their external morphology, internal structure, and physiology, but when it comes to the sexual mode of reproduction, they share a similar pattern."
- **Analysis**: This statement is correct. While plants, animals, and fungi are structurally and functionally different, they all reproduce sexually through the formation of gametes (male and female), which fuse to form a zygote.

2. **Statement 2**: "In annual or biennial plants, there is a clear-cut vegetative reproductive and senescent phase, but in perennial species, it is very difficult to nearly define the phases."
- **Analysis**: This statement is also correct. Annual and biennial plants have distinct life cycles, while perennial plants have longer lifespans, making it harder to define specific phases of growth and reproduction.

3. **Statement 3**: "In animals, the juvenile phase is followed by morphological and physiological changes prior to the active reproductive behavior."
- **Analysis**: This statement is true. Animals undergo a juvenile phase where they grow and develop before reaching maturity and being able to reproduce. This phase is marked by various changes.

4. **Statement 4**: "The female of the marsupial mammals exhibits cyclical changes in the activity of ovaries and accessory ducts as well as hormones during the reproductive phase."
- **Analysis**: This statement is incorrect. The cyclical changes in the reproductive system, including the activity of ovaries and hormonal changes, are characteristic of placental mammals, particularly in primates (termed as the menstrual cycle). Marsupials do not exhibit this cyclical pattern in the same way.

### Conclusion:
The incorrect statement is **Statement 4**.

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