7. Define the operation symbol “ * " to mean $a * b=\frac{a+b}{a b}$ (where $a$ and $b$ are not 0).
Given the following two conclusions:
(1) The operation “ * " satisfies the commutative law;
(2) The operation “ * " satisfies the associative law.

Which of the following is correct? ( ).
(A)(1)
(B)(2)
(C)(1)(2)
(D) None

Output the translation result directly while preserving the original text's line breaks and format.
7. $\mathrm{A}$