Which of the following best describes how a species changes over time?
A.
Members of a species that are best adapted to survive and members with unfavorable traits both produce the same number of offspring.

B.
Members of a species that are best adapted to survive produce offspring with similar characteristics, while members with unfavorable traits do not survive.

C.
Diversity among members of the species causes all members to stop producing offspring.

D.
Members of a species with unfavorable traits produce offspring with similar characteristics, while members best adapted to survive do not reproduce.