Lifespan refers to the earliest age (in months) that Dandie Dinmont Terrier dogs can die on Showdog.com
The "General" factor takes into account such things as show shine and temperament in addition to the other genetic traits.
The sit for exam is a modified version of the Stand for Exam. It is generally used in novice level classes and requires the handler to order the dog to sit and then to move away from the dog the length of the leash. The judge will then approach the dog and pet the dog's head.