Harrison$-$Charles Electronics makes a wide variety of tiny electronic components known as 'transistors'. Each transistor type that Harrison$-$Charles Electronics makes is identified by a unique $5-$digit alpha$-$numeric SKU identifier. RCNEV, $372$O$1,$ and M$0$XHS are three examples of Harrison$-$Charles Electronics's five$-$digit SKU identifiers. Which MySQL core data type is most appropriate for these SKUs?

$-$INT

$-$INT$(5)$

$-$CHAR$(5)$

$-$BLOB

$-$NVARCHAR$(7)$