16. A student is using a straw to blow bubbles into a calcium hydroxide solution. The carbon dioxide in the student's breath is reacting with the water to form an acid, which
begins to neutralize the basic solution. Which of the following best describes the initial
change in pH of the solution?
A. increase in pH toward a pH of 7
B. increase in pH away from a pH of 7
C. decrease in pH toward a pH of 7
D. decrease in pH away from a pH of 7

Which of the following factors would not contribute to allopatric speciation? a) a population becomes geographically isolated from the parent population.b) the separated population is small, and genetic drift occurs.c) the isolated population is exposed to different selection pressures than the ancestral population.d) different mutations begin to distinguish the gene pools of the separated populations.e) gene flow between the two populations is extensive.