What happens if a Base class constructor throws an exception? Does the Derived object get created?

If a base-class constructor throws an exception, construction of the derived object does not complete successfully. The derived constructor body is not reached because the base portion of the object must be initialized before the derived portion. The runtime propagates the exception according to the language's exception rules. From a design perspective, constructors should validate required state and establish invariants, but they should generally avoid complex external operations that can make object creation unpredictable.