A region $R$ in the ( $x , y$ )-plane is defined by the simultaneous inequalities
$$\begin{array} { r }
y - x < 3 \\
y - x ^ { 2 } < 1
\end{array}$$
Which of the following statements is/are true for every point in $R$ ?
I $- 1 < x < 2$\\
II $\quad ( y - x ) \left( y - x ^ { 2 } \right) < 3$\\
III $y < 5$
A none of them\\
B I only\\
C II only\\
D III only\\
E I and II only\\
F I and III only\\
G II and III only\\
H I, II and III