Crusts and uppermost mantle
The correct answer is b. Release of short-chain fatty acids.
The intestinal microflora is complex ecosystem which contains over 400 bacterial species.That microflora is capable of fermenting indigestible carbohydrates (dietary fiber) to short-chain fatty acids such as acetate, propionate, and butyrate.
For an organism to be classified in the animal kingdom it is necessary for that organism to be eukaryotic and multicellular. In addition, he must not be able to produce his own food (he must be heterotrophic), and must eat by eating food taken from the environment.
To be classified in the dilo arthropoda, the organism must have an external skeleton, a segmented body and articulated legs.
To be classified in the insect class, the organism must have a separate body in the head, chest and abdomen, have two antennae, two pairs of wings and three pairs of legs.
