The correct answer is - Birth rate will decrease.
In the past few decades, the birthrate, on a global scale, is decreasing. This doesn't mean that the population is shrinking though, on contrary, it is growing, but the tempo of growing is slowing down. Also, there's variations from one region to another, and while most of the world is experiencing significantly lower birthrates than few decades ago, Africa still has a very high one, with only very slightly reduction of it. Still, according to the prognosis for the next decades, the birthrate, on a global scale will continue to lower down little by little.