Mantle, foot and shell are the characteristics of
Nautilus
Echinus
Limulus
Euplectella
A.
Nautilus
Mantle, foot and shell are characteristics of a mollusc. Nautilus is a mollusc, it is a tetrabranch cephalopod. The shell is external and coiled over the head. Nauctilus is always active at night and rests on bottom during day.