What is the correct way to convert the following exact expression into the big$-$Oh notation?

$1/4$ n$^3-2/3$ n$^2+5/2$ n $-3$

Question $5$ options:

Locate the linearly growing term, n$,$ and ignore the constant coefficient $5/2.$

Locate the fastest growing term, n$^3,$ and ignore the constant coefficient $1/4.$

Locate the term, n$^2,$ and ignore the constant coefficient $2/3.$

Simply ignore the constant $3.$