Final answer:
The correlation coefficient of 0.55 represents the strongest correlation.
Step-by-step explanation:
The correlation coefficient measures the strength and direction of the relationship between two variables. In this case, we are looking for the strongest correlation coefficient. The value closest to 1 (either positive or negative) indicates a strong relationship.
Out of the given options, the correlation coefficient of 0.55 represents the strongest correlation since it is closer to 1 compared to the other options.
Therefore, option b. 0.55 is the correct answer.