Which one of the following is not important for individual health?

Priya's mother uses iodised salt at home. One day while cooking,Priya asked her mother about iodised salt. She said people who do not use iodised salt suffer from deficiency of iodine which leads to goitre and hypothyroidism.
$(a)$ What are the physical symptoms of goitre and hypothyroidism?
$(b)$ How will you inform others about the importance of iodised salt?
$(c)$ Is iodine a metal or a non-metal?
$(d)$ What are the physical properties of iodine?
$(e)$ What is the difference between iodised salt and normal salt?

We should not allow mosquitoes to breed in our surroundings because they :

What are communicable diseases?

Which one of the following causes kala-azar?

Name the organism causing the following diseases:
$(i)$ Kala-azar
$(ii)$ Sleeping sickness