Why would it be impossible to kill a cockroach by holding its head down underwater?
A.Cockroaches have lived for many centuries and are tolerant to many dangers
B.Cockroaches can survive without oxygen for many hours
C.Cockroaches take in air through holes situated elsewhere away from the head
D.Cockroaches have no blood and respire anaerobically

Hint: Cockroaches are insects that belong to the phylum Arthropoda. They are one of the ancient groups of organisms that have been said to have originated 320 million years ago.

Complete answer:
Size of cockroaches is more or less similar to the size of the thumbnail though few species are larger. They consist of a small head and a flattened body which is reddish brown in colour. Few of the distinct body parts include compound eyes, two pairs of wings and long and flexible antenna. The mouth is located below the head and consists of a mandible for chewing, touch and taste receptors and salivary glands. The external surface of the body consists of a tough exoskeleton which also contains a calcium carbonate coating that protects the internal organs. The body is also coated with wax to repel water. The cockroach breathes through small holes that are present on its body and also consists of an open circulatory system.

Hence, the correct answer is option (C)

Note: Cockroaches are widely used as insect models in laboratories both for research and educational purposes because they can be found easily and are simple to raise. Characteristics such as its biological clock, behavioural ecology, spatial orientation and activity rhythms are studied extensively.