A. For every 100 messages, 80 would be labelled correctly as 'Label X', and 20 would be labelled incorrectly.

B. For every 100 messages which should have been labelled as 'Label X', 80 were labelled and 20 were missed.

C. For every 100 messages, 20 would be labelled correctly as 'Label X', and 80 would be labelled incorrectly.

D. For every 100 messages which should have been labelled as 'Label X\ 20 were labelled and 80 were missed.