Answer:
Causal
Step-by-step explanation:
An independent grocer who wants to know if cocktail and tartar sauce would sell better if the two products were moved from the salad dressing section of the store to a display next to the seafood selection would most likely use causal research. Causal research is also known as explanatory research, where we investigate the nature and extent of cause and effect relationship between certain variables. We try to evaluate the effect of one variable on another variable as it has been seen in this given scenario. In this type of research, we focus to evaluate a situation or particular issue and problem under a controlled settings and environment and explain the relationship between the different variables involved in that issue or problem