Answer :
Based on the fact that Pretorius wanted the widows to identify other widows who were exploited, this is a C. Snowball sampling technique.
What is the snowball sampling technique?
This is a technique where those who are being studied are used to find other people to be studied because the original ones might know others in their situation.
The widows in this instance were used to find other widows who could have been exploited so this is snowball sampling.
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