Which arrangement connects two or more cylinders in line for gas delivery?

• A. Manifold system
• B. Regulator
• C. Adjusting screw
• D. Needle valve

Answer: (A)

In gas-delivery setups, connecting two or more cylinders so they feed into a single outlet is done with a manifold system. It ties multiple cylinders to a common line, providing a unified supply and, often, features like check valves to prevent backflow and regulators to maintain a stable downstream pressure. A regulator, needle valve, or adjusting screw serves to control pressure or flow on a single source or valve, not to combine multiple cylinders into one line.