Step 1: Chordata naa 4 mukhhy lakshan.
(i) Notochord, (ii) Dorsal hollow nerve cord, (iii) Pharyngeal gill slits, (iv) Post-anal tail - chaareo Chordates naa defining features.
Step 2: Gills nii gaabajudi = Chordate feature nathi.
Pharyngeal gill slits (gills) = Chordate feature che. Gills no abhav = Chordata ma hoy nahi - e statement galat (NON-feature).
Step 3: ઉttaar.
\\[ \boxed{oxed{ ext{Gills naa abhav = Chordate feature nathi}} \} \]