In which sentence is the underlined clause an adjective clause?

a. In many countries in the world, measles was eradicated when a vaccine was developed in 1963.
b. Typhoid fever is a disease that spreads when food or water is infected with deadly bacteria.
c. Whoever is exposed to parasite-carrying mosquitoes can contract the disease malaria.
d. Chicken pox, which causes bumps on the skin, can be spread through coughs and sneezes.

Option D is the correct answer.

Explanation: The adjective clause is " which causes bumps on the skin".

Adjective clause is used to modify noun and pronoun in a sentence in order to give further description of the noun or pronoun. In this case "chicken pox" is the noun while the adjective clause gives more information about chicken pox by saying " which causes bumps on the skin" anyone who sees the clause will get a clear view of chicken pox.

Adam Smith

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