Which one feature is common to leech, cockroach and scorpion?

Step-by-step solution

Nephridia is the chief excretory organ of Annelida and is present in leech and absent in Arthropoda. The antennae are present in the cockroach and absent in leech and scorpion. The formation of a prominent head is called cephalization and is absent in leech and present in cockroach and scorpion. The presence of the ventral nerve cord is characteristically seen in all invertebrates. The Annelida and Arthropoda are invertebrates and hence all three pose the ventral nerve cord with the anterior region connecting cereb