Answer:
Observers ahead of the wave observe an apparent increase in wave frequency
Explanation:
This is the Doppler Effect. The frequency of a wave increases when the source approaches the observer and decreases as the source recedes.
B, C, and D are wrong. Observers behind the source notice a decrease in frequency.
Speciation is the
process by which new and distinct species are formed. One of the most important
factors necessary for speciation to occur is the genetic isolation of two
populations. This genetic isolation can, over long periods of time, cause these
two groups to become genetically incompatible. Factors that can lead to this
genetic isolation include geographic separation and hostility among population
groups.
C. Changes to biodiversity can positively and negatively affect an ecosystem.