can someone help me?

Answer:
Option a)
Explanation:
On a option, says that this code is for finds the average. On the last line, n1 + n2 + n3, all this divide by 3. But, for the hierarchy of operations and the lack of parenthesis, the code divide n3 by 3 and then add the numbers n1 and n2 to the result.
Is not the same:
15 + 24 + 9 / 3 = 42
That
(15 + 24 + 9) / 3 = 16