Brittle materials are materials that show very little or no plastic deformation before fracture. When a tensile force is applied to a brittle material, it undergoes elastic deformation until it reaches its elastic limit. Beyond the elastic limit, the material fractures without any significant plastic deformation. Therefore, the correct answer is option 'A' - brittle materials.

Explanation:

1. Brittle materials:
- Brittle materials are characterized by their lack of ductility or ability to deform plastically.
- They have limited or no plastic range beyond their elastic limit.
- Examples of brittle materials include glass, ceramics, and some types of polymers.

2. Elastic limit:
- The elastic limit is the maximum stress or force that a material can withstand without undergoing permanent deformation.
- It is the point beyond which the material no longer returns to its original shape after the applied stress is removed.

3. Plastic deformation:
- Plastic deformation refers to the permanent change in shape or size of a material under the influence of an external force.
- In the context of this question, it specifically refers to the ability of a material to undergo significant plastic deformation before fracture.

4. Elastic materials:
- Elastic materials are those that can deform under the influence of external forces and return to their original shape when the forces are removed.
- These materials have a significant elastic range, where deformation is reversible, before reaching their elastic limit.
- Examples of elastic materials include rubber and certain types of polymers.

5. Elastomers:
- Elastomers are a specific type of elastic material that exhibits high elasticity and can undergo large elastic deformations.
- They can stretch and recover their original shape due to their unique molecular structure.
- Examples of elastomers include natural rubber and synthetic rubber.

In summary, materials that show very small plastic range beyond their elastic limit are classified as brittle materials. These materials fracture without undergoing significant plastic deformation.