#!/usr/bin/perl -w

use strict;
use warnings;
use Data::Dumper;

my @arA = qw( lion tiger dog cat snake );
my @arB = qw( tiger dragon lion );
my @arC = qw( dog phoenix );

my %all;

# This is the list of arrays we want to compare against "arA",
# where the key is the label, and the value is the corresponding
# array reference.
my $p = {
    'from Array B' => \@arB,
    'from Array C' => \@arC,
};

foreach my $elA (@arA) {
    foreach my $lbl (keys %$p) {
        map { ($elA eq $_) and push @{$all{$elA}}, "$_ - $lbl" } @{$p->{$lbl}};
    }
}

print Dumper %all;
# Then do some other things with %all...