Quiz: Entry and Exit Times

Node $v$ has tin[v] = 3 and tout[v] = 10. Node $u$ has tin[u] = 5 and tout[u] = 8. What is the relationship between $v$ and $u$?

1. A.$u$ is an ancestor of $v$
2. B.$v$ is an ancestor of $u$
3. C.$v$ and $u$ are in different subtrees
4. D.$v$ and $u$ are siblings