Real numbers $x$ and $y$ satisfy $x+y=4$ and $x\cdot y=-2$. What is the value of $x+\frac{x^{3}}{y^{2}}+\frac{y^{3}}{x^{2}}+y$? (2020 AMC 10A Problem, Question \#14) 
选项为:A:$$360$$  B:$$400$$  C:$$420$$  D:$$440$$  E:$$480$$  请回答其中一个选项.