**Core Concept**
The Kennedy Classification is a system used to categorize the design of removable partial dentures (RPDs) based on the distribution of the remaining natural teeth in the arch. It helps in determining the type of RPD to be used in a particular case. The Kennedy Classification includes Class I, II, III, IV, and V, with Class II being one of the most common configurations.

**Why the Correct Answer is Right**
In a Kennedy Class II edentulous arch, the RPD is designed to support the mandibular canine and first molar on one side of the arch and the second molar on the other side. This configuration is known as the "tripod" configuration because it provides three main points of support: the mesial surface of the first molar, the distal surface of the second molar, and the canine area. This tripod configuration provides excellent support and stability to the RPD, making it a reliable choice for patients with a Kennedy Class II edentulous arch.

**Why Each Wrong Option is Incorrect**
**Option A:** Bilateral refers to a configuration where the RPD is supported on both sides of the arch, which is not characteristic of a Kennedy Class II edentulous arch.

**Option C:** Quadrilateral is not a recognized configuration in the Kennedy Classification system.

**Option D:** Unilateral refers to a configuration where the RPD is supported on only one side of the arch, which is not suitable for a Kennedy Class II edentulous arch.

**Clinical Pearl / High-Yield Fact**
When designing an RPD for a Kennedy Class II edentulous arch, it's essential to ensure that the tripod configuration is maintained to provide optimal support and stability to the prosthesis.

**✓ Correct Answer: B. Tripod**