Spiracles of $Cockroach$ which are larger and always kept open are

The figure given below shows the reproductive system of a female cockroach. The correct labellings indicated by alphabets $(A, B, C)$ are respectively:

In male cockroaches,sperms are stored in which part of the reproductive system?

Which enzyme is present in the saliva of a cockroach?

Which of the following statement$(s)$ is/are correct regarding the respiratory system of a cockroach?
$(i)$ It consists of a network of trachea that open through $12$ pairs of small holes called spiracles present on the lateral side of the body.
$(ii)$ Thin branching tubes carry oxygen from the air to all the parts.
$(iii)$ The opening of the spiracles is regulated by sphincters.
$(iv)$ Exchange of gases takes place at the tracheoles by diffusion.

The body cells in cockroach discharge their nitrogenous waste in the haemolymph mainly in the form of