Answer
True
Work Step by Step
Let $\begin{bmatrix}
a & b & c \\ 0 & d & e\\ 0 & 0 & f
\end{bmatrix}$ be the vector space of $3 × 3$ upper triangular matrices
We can rewrite as $aE_{11}+bE_{12}+cE_{13}+dE_{22}+eE_{23}+fE_{33}$
Hence, matrices in the set $S=E_{11},E_{12},E_{12},E_{22},E_{23},E_{33}$ span the vector space.
The statement is true.