The organisms which cause diseases in plants and animals are called

Options

A. pathogens
B. vectors
C. insects
D. worms

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the organisms responsible for causing diseases in both plants and animals.

2. **Identifying the Term**: The organisms that cause diseases are known as "pathogens." This term encompasses a variety of disease-causing agents.

3. **Types of Pathogens**: Pathogens can include various types of organisms such as bacteria, viruses, fungi, and parasites. Each of these can infect plants or animals and lead to disease.

4. **Examples of Diseases**: For instance, in animals, pathogens can cause diseases like tuberculosis (TB), while in plants, they can lead to conditions like blight or rust.

5. **Conclusion**: Therefore, the answer to the question is that the organisms which cause diseases in plants and animals are called **pathogens**.

---