Two identical glass spheres filled with air are connected by a horizontal glass tube. The glass tube contains a pellet of mercury at its mid-points. Air in one sphere is at 0°C and the other is at 20° If both the vessels are heated through 10°C, then neglecting the expansions of the bulbs and the tube

• A. the mercury pellet gets displaced towards the sphere at lower temperature.
• B. the mercury pellet gets displaced towards the sphere at higher temperature.
• C. the mercury pellet does not get displaced at all
• D. the temperature rise causes the pellet to expand without any displacement.