Question

Spiders are closely related
A. Housefly
B. Termites
C. Ant
D. King crab

Answer 1

Hint: Spiders are arthropods that belong to the order Aranea of the class Arachnida. They have eight jointed legs, jaws with fangs that can inject venom, and spinnerets that are meant for secreting spider silk thatforms spider webs. Their body is segmented and covered with a cuticle made up of chitin.

Complete answer:
-Option (A) is incorrect. Housefly belongs to the order Diptera of the class Insecta. It is not closely related to spiders because they both are grouped into a separate class and also houseflies possess a pair of wings while spiders do not possess wings.
-Option (B) is incorrect. Termites belong to the order Blattodea of the class Insecta. Termite being a social insect is kept in the order in which cockroaches are kept while all other social insects are kept in the order Hymenoptera.
-Option (C) is incorrect. Ant belongs to the order Hymenoptera of the class Insecta. Ant possesses antennae while spiders do not possess antennae. Also, the body of an ant is divided into three regions i.e., head, thorax, and abdomen while the body of the spider is divided into parts i.e., cephalothorax and abdomen. Thus, spiders are not related to an ant.
-Option (D) is correct. King crab is a marine arthropod. Crabs and spiders are classed together in a group called Chelicerata. Their body plan consists of two tagmata, the prosoma, and the opisthosoma. The presence of chelicerae or jaws with fangs (giving this group its name) is the characteristic feature of the members of this group.

Hence, the correct option is (D).

Note:
The suborder Chelicerata under the phylum Arthropoda includes sea spiders, arachnids (crab, spiders, scorpions). King crab is a marine arthropod that belongs to the order Xiphosura of the subphylum Chelicerata in the phylum Arthropoda. It is closely related to spiders and scorpions.