A Planned Quasi-Experimental Study Using a Nonequivalent Control Group Design

A planned quasi-experimental study using a nonequivalent control group design has several extraneous variables that threaten its internal validity. The nurse researcher's actions should be based on which understanding?

A) The results of the study will not be statistically significant.
B) The random assignment of subjects to groups will nullify the intervening variables.
C) The study should be strengthened by controlling intervening variables.
D) Because observation rather than causation is the purpose of the study, no action is necessary.