**Answer:** Test cases for Sum(int a, int b) method.

**Positive Cases**:

**Only int data type is accepted:**Need to test if Sum () method accept only int data type as a parameter.**Only addition function accepted:**Method should return only addition of two numbers. Verify if the output value is equivalent to sum of the input.

**Negative Cases:**

**Verify for non –int type data:**Verify if variable is a numeric and int type only and do not accept alpha characters or others.**Test boundary conditions:**int data type has a range e.g. -32,767 to 32,767. So, we need to test Sum() function with boundary conditions for example 32,767, 32,768 and -32,766 etc.