Select the option in which numbers are related in the same way as are the numbers of following set. (32, 54, 43)

(31, 33, 32) (11, 21, 25) (22, 37, 57) (72, 56, 54)

(31, 33, 32)

(1st number + 2nd number) ÷ 2  =  3rd number (32, 54, 43)    →     (32 + 54) ÷ 2  = \(\frac{86}{2}\) =  43 Similarly, (31, 33, 32)    →     (31 + 33) ÷ 2  =  \(\frac{64}{2}\)  =  32