Answer would be $I$ and $II$ relationship. i.e. $I$ and $II$ are Invalid Tables for the given ER Diagram.
Because There is Many to One relationship from $P$ to $T$ in the ER Diagram. So, An element $p_1$ of $P$ can be related to at most One element of $T$ and An Element of $T$ can be related to any number of elements of $P$. So, Seeing $I$ and $II$ relationships, $p_1$ is related to $t_1$ and $t_2$. Thus, These are Invalid RDBMS Tables for the Given ER Diagram.
Coming to $III$, It is fine. There is Many to Many relationship from $P$ to $Q$ in the ER Diagram. So, An element $p_1$ of $P$ can be related to any number of elements of $T$ and An Element of $T$ can be related to any number of elements of $P$.