use strict;

my (%first, %second, %third);

while (<DATA>) {
    my ($first, $second, $third, $fourth) = split ',';
    print unless exists $first{$first} and exists $second{$second} and exists $third{$third};
    $first{$first}++;
    $second{$second}++;
    $third{$third}++;
}

__DATA__
A1, B1, C1, first record
A2, B2, C2, second record
A5, B2, C3, third record
A4, B1, C3, fourth record
A1, B3, C5, fifth record
A2, B3, C5, sixth record
A3, B1, C2, seventh record
A4, B2, C4, eight record
A1, B3, C4, nineth record
A2, B1, C1, tenth record

##</code><code>##

A1, B1, C1, first record
A2, B2, C2, second record
A5, B2, C3, third record
A4, B1, C3, fourth record
A1, B3, C5, fifth record
A3, B1, C2, seventh record
A4, B2, C4, eight record