The Smooth Fox Terrier
The Smooth fox terrier is perfect for the active senior; they love being loved, and want to experience every moment of their day with their owner. They have a short flat coat and are small, compact, and muscular. The fox terrier is very easy to train, and loves to play fetch!
Source: akc.org
They have one misgiving though. Fox Terriers were initially bred as a hunting dog, and if not trained correctly on the leash, will give their owners a run for their money when pulling.