Which factors are responsible for development of disease in a plant?
A. Susceptible host , B. Aggressive pathogen, C. Conducive environment
D. Excess of fertilizer

Options

A. A and B
B. B and C
C. C and D
D. A, B, C

Answer

To determine the factors responsible for the development of disease in a plant, we can analyze the options provided:

1. **Susceptible Host (A)**: A plant that is vulnerable or has a genetic predisposition to certain diseases can be considered a susceptible host. When a pathogen encounters such a host, the likelihood of disease development increases significantly.

2. **Aggressive Pathogen (B)**: The presence of a pathogen that is particularly virulent or aggressive can lead to disease. Pathogens such as fungi, bacteria, and viruses can infect plants and cause diseases, especially if they have mechanisms to bypass the plant's defenses.

3. **Conducive Environment (C)**: Environmental conditions play a crucial role in disease development. Factors such as humidity, temperature, and soil conditions can either promote or inhibit the growth of pathogens. A conducive environment can facilitate the spread and severity of a disease.

4. **Excess of Fertilizer (D)**: While excess fertilizer can lead to nutrient imbalances and stress in plants, it is not a direct cause of disease development. However, it can make plants more susceptible to diseases by weakening their overall health.

Based on this analysis, the factors responsible for the development of disease in plants are:
- A. Susceptible host
- B. Aggressive pathogen
- C. Conducive environment

**Final Answer**: A, B, and C are responsible for the development of disease in a plant.

---