Question

Which of the following is a singleton set?

• A. $\{x:|x|=1;x\in Z\}$
• B. $\{x:|x|=5;x\in N\}$
• C. $\{x:x$ is even prime number greater than $2\}$
• D. $\{x:x=y+2$ where $y$ is natural number such that $2<y<5\}$

Answer 1

The correct option is B $\{x:|x|=5;x\in N\}$

$\left(a\right)$ Set $=\{-1,1\}$
$\left(b\right)$ Set $=\left\{5\right\}$
$\left(c\right)$ Set $=\left\{\right\}$
$\left(d\right)$ Set $=\{5,6\}$
So, option $\left(b\right)$ is correct