The entrained concrete is used in lining walls and roofs for making A. Heat insulated B. Sound insulated C. Neither (A) nor (B) D. Both (A) and (B)

The correct answer is: Both (A) and (B)

Entrained concrete is concrete that has air bubbles intentionally added to it. These air bubbles act as insulation, reducing heat transfer and sound transmission. Entrained concrete is often used in lining walls and roofs to improve the thermal and acoustic properties of a building.

Here is a brief explanation of each option:

• Heat insulated: Entrained concrete is a good insulator of heat. The air bubbles in the concrete trap air, which is a poor conductor of heat. This helps to keep the building cool in the summer and warm in the winter.
• Sound insulated: Entrained concrete is also a good insulator of sound. The air bubbles in the concrete absorb sound waves, which helps to reduce noise levels inside the building.

I hope this helps! Let me know if you have any other questions.