Given the following code $($with line numbers provided for clarity$)$:

$1$: def readAge$($filename$)$:

$2$: year $=2021$

$3$: infile $=$ open$($filename$)$

$4$: strAge $=$ infile.readline$()$

$5$: age $=$ year $-$ int$($strAge$)$

$6$: return 'born in $\{\}\text{'}.$format$($age$)$

Which lines could possibly throw an exception?

Given the following code $($with line numbers provided for clarity$)$:

$1$: def readAge$($filename$)$:

$2$: year $=2021$

$3$: infile $=$ open$($filename$)$

$4$: strAge $=$ infile.readline$()$

$5$: age $=$ year $-$ int$($strAge$)$

$6$: return 'born in $\{\}\text{'}.$format$($age$)$

Which lines could possibly throw an exception?

$1$ and $2$

$2$ and $4$

$1$ and $4$

$3$ and $5$

None of the above