Animals Questions and Answers

Answer: B

The bird is the Weaver bird.

The male weaver bird weaves an elaborate hanging nest from strips of grass and leaves, often several of them. Females inspect the nests and choose the one they like best to lay their eggs in, so a well-built nest helps the male win a mate. NCERT's EVS books describe this behaviour.

The tailor bird stitches leaves together to make its nest, the sunbird builds a hanging pouch, and the Indian robin nests in holes and crevices; none follows this pattern of male building and female choosing.

Answer: A

Both (A) and (R) are correct and (R) explains (A).

The male silk moth can find a female from a long distance, even kilometres away, by her smell, as NCERT's EVS chapter on animals' senses describes. The reason gives the explanation: female insects such as the silk moth release chemicals called pheromones, which males detect with their antennae and follow to the female.

Since the pheromone is the 'smell' the male follows, (R) directly explains (A), which rules out the other options.

Answer: B

The incorrect statement is a herd has 20 to 25 female elephants and their young ones.

The NCERT EVS textbook describes an elephant herd as made up of females and young ones, usually about 10 to 12 females with their calves, led by an older female. Young males stay with the herd until they are about 14-15 years old and then leave to live alone or in small groups.

So statements 1, 3 and 4 match the textbook, and only the figure of 20 to 25 females is wrong.

Answer: B

(A) and (B) both are wrong.

Crows build their nests high up in trees, not on very low branches. And it is the tailorbird, not the weaver bird, that stitches leaves together to make its nest; the weaver bird weaves a hanging nest from strips of grass and leaves.

Since both statements are false, the options calling either one correct are ruled out.