Which two numbers should be interchanged to make the given equation correct? (NOTE: Numbers must be interchanged and not the constituent digits e.g. if 2 and 3 are to be interchanged in the equation 43 × 3 + 4 ÷ 2, then interchanged equation is 43 × 2 + 4 ÷ 3)
74 – 52 + (39 ÷ 13) × 16 + (14 ÷ 2) = 106

Given: 74 – 52 + (39 ÷ 13) × 16 + (14 ÷ 2) = 106

From the given options - 
Logic: After interchanging 52 and 39 we get following equation 
74 – 39 + (52 ÷ 13) × 16 + (14 ÷ 2) = 106
Following BODMAS:
74 – 39 + 4 × 16 + 7 = 106

74 – 39 + 64 + 7 = 106

145 – 39 = 106

106 = 106
Final Answer: (a) 52 and 39 ​​