Answer:
Clam.
Step-by-step explanation:
Arthrophoda is largest phylum of the non-chordata. They are the segmented animals with jointed appendages. Their body is covered by exoskeleton and contains spiracles and body surface for respiration.
Insect, spider, crab and scorpion all are included in the phylum arthropoda. Clam is a bivalve shell that is included in the phylum mollusc. The body of clam is covered with an outer shell and their shells are connected by the abductor muscle. Hence, they are involved in phylum arthropoda.
Thus, the correct answer is option (b).