(a) Marine habitat
(b) Bilateral symmetry with cephalization
(c) Haemocoel as pricipal body cavity
(d) Eyes similar to that of vertebrates
$\begin {array} {1 1} (1)\;Jelly\: fish & \quad (2)\;Cuttle\: fish \\ (3)\;Silver\: fish & \quad (4)\;Dog\: fish \end {array}$
