Correct option is C
The main requirements of the insulating materials used for cables are as follows:
1. High Insulation Resistance: The material should have high insulation resistance to prevent leakage currents and ensure safety.
2. Low Hygroscopicity: The insulating material should have low hygroscopicity, meaning it should not absorb moisture from the environment. Moisture can reduce the insulation resistance and lead to the degradation of the insulating properties.
3. Tenacity: This refers to the material's ability to withstand mechanical stresses without breaking or deteriorating. It is crucial for the insulation to be mechanically strong and durable to protect the conductors and maintain the integrity of the cable under various conditions.
4. Elasticity: While some degree of flexibility and elasticity is important to allow for bending and handling of the cables, excessive elasticity is not a primary requirement. The material should balance flexibility and rigidity to maintain its insulating properties.
Given these points, tenacity (c) is the primary requirement among the options provided, as it ensures the mechanical strength and durability of the insulating material.
