Fill in the blank with either $in$ or $!in$ to make the statement true.

$\{7{\}}_{4+3,7+3}$

Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A$.$ The $!in$ symbol should be used because $\{7\}$ is a set and none of the elements in $\{4+3,7+3\}$ is a set.

B$.$ The $!in$ symbol should be used because $$ is an element of the set.

C$.$ The $in$ symbol should be used because $\{7\}$ and $\{4+3,7+3\}$ are equal sets.

D$.$ The $!in$ symbol should be used because $$ is not an element of the set.

E$.$ The $in$ symbol should be used because $$ is not an element of the set.

F$.$ The $in$ symbol should be used because $$ is an element of the set.