In the past, mass extinctions encouraged the rapid evolution of surviving species
select one:
a. because they killed all organisms that had co-evolved
b. becaused they apred all organisms that had evolved at the same time
c. by making new habitats available to them
d. by changing developmental genes

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.

b c a d mark me