Q. What will be the output obtained by "shift ()" in the given code of JavaScript?

var a =[];  
a.unshift(5);  
a.unshift(22);  
a.shift();  
a.unshift(3,[4,5]);  
a.shift();  
a.shift();  
a.shift();  

• (A) Exception is thrown
• (B) [4,5]
• (C) [3,4,5]
• (D) 5