The value of is:  $$\sqrt{16+\sqrt{80+\sqrt{5000 - 4999}}}$$ .

Correct option is B

Given: 

​$$\sqrt{16+\sqrt{80+\sqrt{5000 - 4999}}}$$ 

Solution: 

​$$=\sqrt{16+\sqrt{80+\sqrt{5000 - 4999}}} \\ =\sqrt{16+\sqrt{80+\sqrt{1}}}\\ =\sqrt{16+\sqrt{81}}\\ =\sqrt{16+9 }\\ =\sqrt{25 } \\ = 5$$​​