Passing arguments from a file to a bash script

I've got four files:

./
./myscript.sh
./arguments.txt
./test.sh

Inside myscript.sh, I have to run the file test.sh, passing to it the arguments contained inside arguments.txt. myscript.sh is:

-bash
arguments=$(cat arguments.txt)
source test.sh $arguments

This works well *if arguments.txt contains at most one* argument:

firstargument

The substitution is:

-shellsession
++ source test.sh 'firstargument'

But the problem is with two or more arguments. It does this:

-shellsession
++ source test.sh 'firstargument secondargument'

Also, I don't know in advance the number of arguments inside arguments.txt. There can be zero or more.