Researchers wanted to determine if there was an association between the level of happiness happiness of an individual and their risk of diabetes diabetes. the researchers studied 1650 1650 people over the course of 5 5 years. during this 5 5-year period, they interviewed the individuals and asked questions about their daily lives and the hassles they face. in addition, hypothetical scenarios were presented to determine how each individual would handle the situation. these interviews were videotaped and studied to assess the emotions of the individuals. the researchers also determined which individuals in the study experienced any type of diabetes diabetes over the 5 5-year period. after their analysis, the researchers concluded that the happy happy individuals were less likely to experience diabetes diabetes. complete parts (a) through (c). (a) what type of observational study was this? explain.