In the code sample below, a user enters the following input: $"$; sleep $5$; cat $/$etc$/$passwd; echo $".$ Wh be the behavior of this command injection?

import subprocess

import time

def execute$\_$command$($user$\_$input$)$:

command $=$ f$"$echo $\{$user$\_$input $\}"$

result $=$ subprocess.check$\_$output $($command$,$ shell$=$True$)$

return result.decode$("$utf$-8").$strip$()$

user$\_$input $=$ input $("$Enter a value: $")$

output $=$ execute$\_$command $($user$\_$input$)$

print$($f$"$Output: $\{$output$\}")$

a$.$ An error will occur due to an invalid input.

b$.$ The entered value will be echoed back: $"$; steep $5$; cat $/$etc$/$passwd; echo $"$

c$.$ The content of the $/$etc$/$passud file will be displayed after a $5-$second delay.

d$.$ The program will terminate without any output.