Removing alternate elements in a List

Question

What is the most efficient way to remove alternate (odd indexed or even indexed) elements in an List without using a place holder list variable?

A

Answer 1

And another option, similar to Frank's one, but with usage of closures. And it is quicker than Frank's version.

bool isEven = true;            
var newList = list.Where(x => isEven = !isEven).ToList();