Domain of any function is defined by all the values of x for which the given function is valid.
In other words for any function if we put the value of x and we get a unique value of y, then x - values are considered as the domain of the function and y- values as range.
From the given graph we can easily say all the values of x greater than (-3) is the domain set.
The domain is all of the possible x values, and there are none less than -3 in this case, so the answer is B, which shows that x must be greater than or equal to -3.
