The term "duct" means?

• A. Running
• B. Guide, tubular path
• C. Pain
• D. Echo

Answer: (B)

Duct is defined by the idea of a tube that leads substances from one area to another. The term comes from the Latin ducere, meaning “to lead,” which is why a duct functions as a conduit or channel. In the body, ducts carry secretions or fluids—like the bile duct moving bile from the liver, or tear ducts carrying tears to the surface. This makes the description of a duct as a guide, tubular path the best fit. The other options don’t capture that sense of a tube that transports something: running implies motion, pain is a sensation, and an echo is a reflected sound.