Picking a single line from a text file by its line number

Question

In a Unix shell, how can I pick a single line from a text file by its line number?

Say I want whatever is at line 3 in animals.txt to be written to stdout (bat bat bat).

monkey monkey monkey
cat cat cat
bat bat bat
horse horse horse

Is there a standard program or simple way to do this?

(There's also the case where the text file does not contain enough lines to contain the line number you ask for)

Answer 1

This is one way:

sed -n '3p' file

Here's another:

head -n 3 file | tail -n 1