Answer:
Focus Group Study
Step-by-step explanation:
Focus group is a small group with diverse people whose reactions are studied by market researchers to analyze attitude towards a particular product, advertising campaign and so on. It is estimated that these reaction represent a large population.
In this case, Martin has suggested that the company should study the reactions by a small group towards the three advertising slogans that the firm is considering.
Consensus can be derived by the responses of this group which is considered to represent the population at large.
Marketing research company should conduct a focus group study.