11, add six and a half to four and a half.
The commutative property is when you change the order but not the answer. To better understand what they are asking you, let's let x=1- 6 * 2 * 1=12; Answer A wouldn't be right because there are no 6,2, or x's. Remember you just change the ORDER not the GROUPING so Answer B is wrong too. Now Answer C and Answer D are left. Now you just need to look at the signs. 6(2) just means 6 TIMES 2 so pick the option with multiplication. So your answer is C. Hope I helped!
Explanation:
Since we have given that

Now, we have to prove it as

Now, start the iterations:

So, first blank will be filled with

Second blank will be filled with

Hence proved.