Wolfram Mathematica：如何在不使用一个元素的情况下复制列表？

Question

E.g。我有list A = {a,b,c,d}

如何在一个命令中不使用list B = A元素获取{b}？

Answer 1

B = Delete[A, 3]

或

B = DeleteCases[A, c]

Answer 2

A = {a, b, c, d};
B = Cases[A, Except[b]]