It would be D. Stratified due to the fact that it couldn't possibly be any of the others. It isn't random because it is only women, Cluster isn't correct either, a cluster would mean "random" people which is the same as different people in a small group. It isn't Convenience due to the fact that "Convenience wouldn't even make sense in this situation. Lastly, Systematic and stratified are really close but one would still be more logical than the other.