What will be in the value of variable <code>res</c

What will be in the value of variable res after execution of the following code?

int a = 5;
int data[3];
data[0] = 10;
int res = a * data[0] / (data[0] = 5);

5
10
25
Result is not defined

Explanation

The correct answer is that the result is not defined; it works similarly to calculating function arguments (without any particular order). That is, an expression is evaluated from right to left, but one compiler can calculate all the operands in advance in any order, and the other can start evaluating the expression and, as necessary, calculate the operands.