Question

which among the following is metalloid? As, Bi ,Cu,Zn

Answer 1

metalloids is b as it shows both metallic and non metallic character

Answer 2

(A metalloid is another term for a semiconductor.) A metalloid is an element which exists properties between metal and nonmetals. The metalloids are 
---
B
Si
Ge
As
Sb
Te and Po 
So according to your question, the correct answer is As
.
.
Hope it helps...