$\begin {array} {1 1} (I)\;Casuarina & \quad (II)\;Vernonia \\ (III)\;Colocasia & \quad (IV)\;Ficus \end {array}$
$\begin {array} {1 1} (1)\;(I),(II) & \quad (2)\;(II),(III) \\ (3)\;(III),(IV) & \quad (4)\;(I),(IV) \end {array}$