I want to know the answer to the following question:
What river is a tributary of the River Thames?
All the background I'm provided with is that "Other long distance paths, linking green spaces, have also been created, including the Capital Ring, the Green Chain Walk, London Outer Orbital Path ("Loop"), Jubilee Walkway, Lea Valley Walk, and the Diana, Princess of Wales Memorial Walk.". Is that enough to answer the question?
Answer: no