Plants can be made disease-resistant by

Options

A. Breeding with their wild relatives
B. Colchicine treatment
C. Hormone treatment
D. Heat treatment

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks how plants can be made disease-resistant. This involves methods that enhance a plant's ability to withstand diseases caused by pathogens.

2. **Exploring the Options**: The provided options are:
- Breeding with their wild relatives
- Colchicine treatment
- Hormone treatment
- Heat treatment

3. **Analyzing Each Option**:
- **Breeding with Wild Relatives**: This method involves crossbreeding cultivated plants with their wild relatives. Wild relatives often possess genes that confer resistance to diseases. By introducing these genes into cultivated varieties, we can enhance their disease resistance.

- **Colchicine Treatment**: Colchicine is a chemical that can induce polyploidy (increase in the number of chromosome sets) in plants. While it can lead to certain desirable traits, it is not primarily used for enhancing disease resistance.

- **Hormone Treatment**: This involves applying hormones to plants to stimulate growth or other responses. While hormones can influence plant health, they do not directly confer disease resistance.

- **Heat Treatment**: This method involves exposing plants to heat, which can damage their cellular structures and denature proteins. It is not a viable method for enhancing disease resistance.

4. **Conclusion**: After analyzing all options, the most effective method for making plants disease-resistant is **breeding with their wild relatives**. This method allows for the introduction of beneficial genes that can help the plant resist diseases.

5. **Final Answer**: Plants can be made disease-resistant by **breeding with their wild relatives**.

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