The red or yellow structure which looks like an open mouth is the ________ .
In the above-mentioned passage, the narrator talks about a phenomenon, not many know of. Batesian mimicry. This is a technique used by the harmless milk snake, to protect itself from the predators preying on it. It displays one of the wonders of nature, by showing the level of intelligence the creature possesses, for survival.
Following the model of the harmless snakes, the legless, blind lizard also mimics using its tail. The tail is red and yellow in colour, which gives it the appearance of a head. There is a mention regarding the colour of the tail in the fourth last line, ''The underside of their tails is usually red or yellow in color and looks like an open mouth'' and thus Option A is the correct answer.
In the other options, ‘limb’ is something that the blind lizards don’t possess, while ‘scales’ don’t find a mention in the passage and ‘head’ is what the lizard needs to protect from the enemies, and thus with reference from the passage, ‘tail’ is the correct answer.