Nutrition in Animals

Cellulose-rich food substances are good source of roughage in
human beings because
(a) human beings do not have cellulose-digesting enzymes.
(b) cellulose gets absorbed in the human blood and converts into fibres.
(c) the cellulose-digesting bacteria convert cellulose into fibres.
(d) cellulose breaks down into smaller components which are egested as roughage.