Solution (source code)

= Solution

Every subspace-<open set> has the form $A\cap U=i^{-1}(U)$ for some $U\in\mathcal T$. <Continuity> of $i:(A,\mathcal T')\to(X,\mathcal T)$ makes every such inverse image open in $\mathcal T'$. Hence $\boxed{\mathcal T_A\subseteq\mathcal T'}$.