Answer:
a. Exposure to fine dust from cutting stone benchtops
Step-by-step explanation:
Silicosis is a disease that arises as a result of engaging in occupation which requires exposure to fine silica dust. This disease affects the lungs because the dust particles are inhaled. Symptoms associated with this disease include, cough, shortness of breath and discoloration of the skin. These symptoms are similar to those suffered by asthmatic patients.
Occupations that require stone cutting or even mining can lead to exposure to these diseases. Therefore, the 22 year old Gold Coast man who was affected by Silicosis was most likely involved in an occupation that exposed him to inhalation of fine silica dust.