Java SE classes are defined as shown below:

class Shape $\{\}$

class Quadrilateral extends Shape $\{\}$

class Triangle extends Shape $\{\}$

If the variables below are declared:

Shape shape$=$new Quadrilateral$\{\}$;

Quadrilateral quadrilateral$=$ new Quadrilateral$()$;

Which of the following statements are correct?

a$.$ The statement Triangle tri$=($Triangle$)$ shape; will fail to compile

b$.$ The statement Triangle tri $=($Triangle$)$ shape; will compile and execute without error

c$.$ The statement shape$=$quadrilateral; will throw an exception at runtime

d$.$ The statement Triangle tri $=($Triangle$)$ shape; will throw an exception at runtime.