The associative property of multiplication states that you can choose any pair of numbers to multiply first when there are more than two numbers being multiplied. This doesn't change the final result:
a . b . c = (a . b) . c = a . (b . c)
So, we see an example of such property in the first option:
7 . (3 . 5) = (7 . 3) . 5
Let's check this is indeed true:
7 . (3 . 5) = 7 . 15 = 105
(7 . 3) . 5 = 21 * 5 = 105
Therefore, the first option is correct.
Notice that the second option uses the distributive property of multiplication over addition:
a . (b + c) = a . b + a . c
The third uses the commutative property of multiplication:
a . b = b . a
The fourth is wrong since zero multiplied by any number is zero, not one:
0 . a = 0, for all values of a.