Which out of the following is the correct file extension

Odd one out

If 38 × 34 = 31, 34 × 58 = 25 and 56 × 67 = 43, then 28 × 32 = ?

Select the option that is related to the third word in the same way as the second word is related to the first word.  

Complete the analogy.

81 : 45 :: 72 : ?

Select the option that is related to the third number in the same way as the second number is related to the first number.

31 : 90 :: 43 : ?

'Excel' is related to 'Spreadsheet Software,' in the same way as 'PowerPoint' is related to '____.'

'Eiffel Tower' is related to 'France', in the same way as 'Great Wall' is related to '____'.