Answer:
We know that our sample is a group of 50 randomly selected students.
First, we want to know the name of the sampling technique.
There are a lot of sampling techniques, but knowing that the students are selected randomly, we can conclude that this is the simple random sampling technique, where each individual is chosen entirely by chance (so all the students have the same probability of being chosen)
Now we want to know if the method is biased or not,
Always that we use the simple random sampling technique, we will have an unbiased sample.