Concept:An arithmetic progression (A.P.) has terms given by Tn=a+(n−1)d, where a is the first term and d is the common difference.Explanation:The 4th term is 13, so:a+3d=13 ... (1)The 10th term is 31, so:a+9d=31 ... (2)Subtract equation (1) from equation (2):(a+9d)−(a+3d)=31−136d=18d=3Substitute d=3 into equation (1):a+3(3)=13a+9=13a=4The 24th term is:T24=a+23dT24=4+23(3)T24=4+69=73Answer:The 24th term is 73, which is option C.