With no explanation, label each line with "O", "other-biologything", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
This
happens
because
``
C.
botulinum
``
produces
a
toxin
which
blocks
the
release
of
acetylcholine
.
This:O
happens:O
because:O
``:O
C.:other-biologything
botulinum:other-biologything
``:O
produces:O
a:O
toxin:O
which:O
blocks:O
the:O
release:O
of:O
acetylcholine:other-biologything
.:O