Using C$++$Which function best represents the number of operations in the worst$-$case?

for$(\%2==1=2\mathrm{.}5f(N)=2N$

$f(N)=5N+2$

$f(N)=6N^{{?}^{{?}^{?}}}2$

$f(N)=8N^{{?}^{{?}^{?}}}2+4i=0$;$i\{$

$if($ numbers$[i]\%2==1)$

factor $=2\mathrm{.}5$

$\}$

$f(N)=2N$

$f(N)=5N+2$

$f(N)=6N^{{?}^{{?}^{?}}}2$

$f(N)=8N^{{?}^{{?}^{?}}}2+4$