A large union needs to gather information from their members

A large union needs to gather information from their members. To save on expenses, they

Solution

A. Assign a randomly generated number from a uniform distribution to each member. Order all the members by the value of their random numbers and select the first hundred names from the reordered list.

The reason for A being answer is that this is the only option that ensures that sample are taken randomly. Although D also ensures randomization but it increases the amount of effort to be put.