When inhaled, crystalline silica can cause scar tissue to form on what organs?
a. eyes
b. heart
c. lungs
d. sinuses?

Option C, Lungs

Explanation:

When silica dust is inhaled it causes silicosis which in severe cases is disabling. When Silica enters the lungs , scar tissues are formed which lead to difficulty in taking oxygen. This problem usually arises when crystalline silica is inhaled continuously for a period of 15 to 20 years. Its symptoms are not visible and thus can only be determined through chest X-Ray. However, after prolonged exposure lung dysfunctions causes breathing problem, fatigue, chest pain or  respiratory failure

Hence, option C is correct

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms

the answer would be   10%