GATE Computer Science (CS) 2018 Shift 1 Solved Paper

Let $\mathit{G}$ be a simple undirected graph. Let ${\mathit{T}}_{\mathit{D}}$ be a depth first search tree of $\mathit{G}$. Let ${\mathit{T}}_{\mathit{B}}$ be a breadth first search tree of G. Consider the following statements:
I. No edge of $\mathit{G}$ is a cross edge with respect to ${\mathit{T}}_{\mathit{D}}$. (A cross edge is $\mathit{G}$ is between two nodes neither of which is an ancestor of the other in ${\mathit{T}}_{\mathit{D}}$ ).
II. For every edge $\left(\mathit{u},\mathit{v}\right)$ of $\mathit{G}$, if $\mathit{u}$ is at depth $\mathit{i}$ and $\mathit{v}$ is at depth $\mathit{j}$ in ${\mathit{T}}_{\mathit{B}}$, then $\left(\mathit{i}-\mathit{j}\right)=1$.
Which of the statements above must necessarily be true?