The seeds that can tolerate drying and can remain viable for years are called orthodox seeds. These seeds are stored at low temperatures by drying them such that the moisture content is less than 10%. The seeds are stored till the next sowing period. Cereal and legume seeds are of orthodox type. Thus the correct answer is option A.

Orthodox seeds are the seeds that can withstand desiccation (drying) and can be stored for long periods under low temperature and low humidity conditions without losing their viability. Recalcitrant seeds, on the other hand, cannot tolerate desiccation and quickly lose their viability if they are dried.

Orthodox seeds are commonly found in cereals and legumes, which are the main sources of food for humans and animals. These seeds have a protective seed coat and are able to survive drying and storage conditions due to their unique characteristics.

Here is a detailed explanation of why the correct answer is option 'A' - Orthodox seed:

1. Orthodox seeds can tolerate desiccation:
- The seeds of cereals and legumes, such as wheat, rice, maize, soybean, and chickpea, are considered orthodox seeds.
- These seeds have a low moisture content and can withstand drying without losing their viability.
- They can be stored for long periods under controlled conditions, such as low temperature and low humidity, without germinating or losing their ability to germinate.

2. Recalcitrant seeds cannot tolerate desiccation:
- Recalcitrant seeds, also known as non-orthodox seeds, cannot survive drying and lose their viability if they are dried.
- Unlike orthodox seeds, they have a high moisture content and are sensitive to desiccation.
- Examples of recalcitrant seeds include those of tropical fruits like mango, avocado, and durian.

3. Importance of orthodox seeds in agriculture:
- Orthodox seeds are crucial for agricultural practices as they can be stored for extended periods, allowing farmers to plant them in subsequent seasons.
- They can be transported over long distances without losing their viability.
- Their ability to withstand drying enables the production of high-quality seeds, which ensures a consistent and reliable food supply.

In conclusion, seeds of different cereals and legumes are classified as orthodox seeds because they can tolerate desiccation and be stored for long periods without losing their viability. This characteristic is essential for their use in agriculture and ensuring a stable food supply.