Which statement correctly differentiates Wye and Siamese appliances?

• A. Wye merges multiple lines into one; Siamese splits one line into multiple.
• B. Wye splits a single line into multiple; Siamese merges several lines into one.
• C. Both are used to monitor water pressure
• D. Siamese is used only for hydrants

Answer: (B)

This question tests how Wye and Siamese fittings route water on the fireground. The key idea is that a Wye splits a single line into multiple branches, while a Siamese merges several lines into one. A Wye has one inlet and two or more outlets, so you can feed two or more hoses from one discharge. A Siamese has two or more inlets and a single outlet, so you can combine water from several sources into one supply line. Therefore, the statement that a Wye splits a single line into multiple lines and a Siamese merges several lines into one is the correct distinction.