Step 1: Analyzing the options.
- Iron Industry: The condition related to working in the iron industry is siderosis, which is a type of lung disease caused by inhaling iron dust. Thus, the correct match is:
\[
\text{Iron Industry} \rightarrow \text{(ii) Siderosis}
\]
- Study of behaviour: The scientific study of human behavior falls under psychology, which is the study of mind and behavior. Thus, the correct match is:
\[
\text{Study of behaviour} \rightarrow \text{(i) Psychology}
\]
- Interval training method: This refers to a method of training that involves alternating periods of intense activity with periods of rest. The rest in interval training is often referred to as incomplete rest because the individual does not completely rest but performs low-intensity activity. Thus, the correct match is:
\[
\text{Interval training method} \rightarrow \text{(iii) Incomplete Rest}
\]
Step 2: Conclusion.
Thus, the correct matching is:
\[
\text{Iron Industry} \rightarrow \text{(ii) Siderosis}
\]
\[
\text{Study of behaviour} \rightarrow \text{(i) Psychology}
\]
\[
\text{Interval training method} \rightarrow \text{(iii) Incomplete Rest}
\]