Question

Which of the following are singleton sets?

$\left\{Evennumberswhichareprime\right\}$

Answer 1

A set containing only one element is called a singleton set.

Given Set:

$\left\{Evennumberswhichareprime\right\}$

A number is said t be prime if it has only two factors, $1$ and itself.

The only even number which is prime is $\left\{2\right\}$ which is only $1$ element.

Hence, the set of $\left\{Evennumberswhichareprime\right\}$ is a Singleton set.