Final answer:
Thread joints use threads and are typically used for components that may need to be disassembled, whereas rivet joints are permanent and do not involve threads. Thread joints are usually faster to assemble than rivet joints.
Step-by-step explanation:
The differences between thread joints and rivet joints are important to understand in the context of mechanical engineering and construction. Option B is the correct choice. Thread joints involve the use of threads, such as in screws or bolts, that allow for components to be assembled and disassembled relatively easily. Whereas, rivet joints do not involve threads and are a more permanent form of fastening, where the rivet is inserted into pre-drilled holes of the parts to be joined and then deformed to hold the parts together, typically requiring destruction of the rivet to disassemble.
Regarding the speed of assembly, thread joints can often be faster to assemble and disassemble because they require no special tools for removal, unlike rivet joints where a riveting process is involved. However, this can vary depending on the specific application and context. Overall, the main distinction lies in the method of fastening and the permanency of the joint.