Please see 7

Which of the following combination of coefficients should the researchers employ to answer the research question for AgeGroup: Researchers were interested in comparing the depression levels for Australian adults from four different age groups (18 to 29; 30 to 39; 40 to 49; and 50 to 59). They suggested that depression levels for 18 to 29 year olds would be lower compared to 30 to 39 year olds. O C18to29 =1, C30to39 = -1, C40to49 = -1, C50to59 = 1 O C18to29 =0, C30to39 = -1, C40to49 = 1, C50to59 = 0 O C18to29 =1, C30to39 = -1, C40to49 = 0, C50to59 = 0 O C18to29 =2, C30to39 = -1, C40to49 = -1, C50to59 = 0