In which situation will the growth rate not become very low immediately even if the death rate is low?

Correct answer: When the birth rate is still fairly high

Correct answer: B, when the birth rate is still fairly high. Population growth depends on the balance between additions and losses. Births add people, while deaths remove people; migration can also add or remove people. If the death rate is low but the birth rate remains fairly high, births are still much greater than deaths, so the population can continue to grow at a noticeable rate. B is correct because a high birth rate offsets the effect of low deaths and keeps natural increase positive. A is wrong because a very low birth rate and negative migration would reduce growth, possibly producing decline. C is wrong because if everyone moved out, the area would lose population rather than maintain growth. D is wrong because a zero base population cannot produce ordinary positive growth without people entering first. Memory cue: compare the birth rate with the death rate; the gap matters.