Answer: simple random sampling
Step-by-step explanation:
Given : The names of 50 contestants are written on 50 cards.
here ,N= 50
So , the probability for each student to get selected = [tex]\dfrac{1}{50}[/tex].
The cards are placed in a bag, and three names are picked from the bag (which is a random action).
Hence, the sampling technique is used is "simple random sampling" .