In the list of tokens, identify 'Person', 'Location', and 'Organisation' and label each accordingly. If the entity spans multiple tokens, use the prefix B-PER, B-LOC, or B-ORG for the first token, and I-PER, I-LOC, or I-ORG for the subsequent tokens of that entity. The beginning of each separate entity should always be labeled with a B-PER, B-LOC, or B-ORG prefix. If the token does not fit into any of the three named categories, or is not a named entity, label it as 'O'. Each line should contain one token and its corresponding label, separated by a colon. Do not combine tokens on your own. The format for each line should be: 'token:label'.

Text: However
,
a
few
days
back
,
security
researchers
revealed
that
many
of
the
top
apps
on
the
Apple
App
store
were
infected
with
malware
.
Answer: 
However:O
,:O
a:O
few:O
days:O
back:O
,:O
security:O
researchers:O
revealed:O
that:O
many:O
of:O
the:O
top:O
apps:O
on:O
the:O
Apple:O
App:O
store:O
were:O
infected:O
with:O
malware:O
.:O