The variety in a species comes through in DNA. When a new and helpful mutation arises, it will help individuals in the species to better . Over the following generations, the new trait will become more prominent in a population (or even essential) since it increases the chances of . (For example, the first bats to fly would have had an advantage over other bats who did not have the new genes necessary. The flight gene likely quickly during the following generations since it is so useful for survival.)

answer-

the statement that f(x) = |x+a| + b has exactly one x-intercept is sometimes correct.

solution-

it solely depends on b, whether the function will have one or two or zero x intercept.

this plot of the given function, f(x) = |x+a| + b will be the basic absolute value graph i.e v shape, with vertex translated to (-a, b), instead of origin.

1-   if b is zero, the graph will have exactly one x-intercept, at x= -a

2- if b is positive, the whole graph will be above the x-axis, hence it will have no x-intercepts.

3- if b is negative, the graph will be below the x-axis, hence it will have two x-intercepts.

∴ the statement is sometimes true.