my @a = qw/A B C D E F/;
my @b = qw/1 2 3 4 5 6/;
my @c = qw/apple orange pomegranate grape/;
my @d = qw/wolf lion dog cat cow ape whale/;

##</code><code>##

[A, 1, apple, wolf]
[A, 1, apple, lion]
[A, 1, apple, dog]
...
[C, 5, pomegranate, ape]
[C, 5, pomegranate, whale]
[C, 5, grape, wolf]
[C, 5, grape, lion]
...
[F, 6, grape, whale]