the population of the coral lophelia pertusa declined significantly around 9,000 years ago in the alboran…

the population of the coral lophelia pertusa declined significantly around 9,000 years ago in the alboran sea and around 11,000 years ago near the mauritanian coast. using the ratio of manganese to calcium, which inversely correlates with ocean oxygenation levels, marine scientist rodrigo da costa portilho - ramos and colleagues evaluated whether oxygenation played a role in the declines of l. pertusa. the researchers concluded that oxygenation may have been important in the alboran sea but not near the mauritanian coast, since \nwhich choice most effectively uses data from the graph to complete the statement?\na. a substantial increase in oxygenation in the alboran sea corresponded with the local decline in l. pertusa, but the opposite relationship between oxygenation and l. pertusa was found near the mauritanian coast\nb. l. pertusa declined in the alboran sea during a period of substantial local decline in oxygenation, but l. pertusa declined near the mauritanian coast during a period of little local change in oxygenation.\nc. oxygenation in the alboran sea was higher before the decline in l. pertusa than after the decline, whereas oxygenation near the mauritanian coast was relatively low both before and after the decline in l. pertusa.\nd. oxygenation in the alboran sea tended to be substantially higher than oxygenation near the mauritanian coast during the period studied.

the population of the coral lophelia pertusa declined significantly around 9,000 years ago in the alboran sea and around 11,000 years ago near the mauritanian coast. using the ratio of manganese to calcium, which inversely correlates with ocean oxygenation levels, marine scientist rodrigo da costa portilho - ramos and colleagues evaluated whether oxygenation played a role in the declines of l. pertusa. the researchers concluded that oxygenation may have been important in the alboran sea but not near the mauritanian coast, since \nwhich choice most effectively uses data from the graph to complete the statement?\na. a substantial increase in oxygenation in the alboran sea corresponded with the local decline in l. pertusa, but the opposite relationship between oxygenation and l. pertusa was found near the mauritanian coast\nb. l. pertusa declined in the alboran sea during a period of substantial local decline in oxygenation, but l. pertusa declined near the mauritanian coast during a period of little local change in oxygenation.\nc. oxygenation in the alboran sea was higher before the decline in l. pertusa than after the decline, whereas oxygenation near the mauritanian coast was relatively low both before and after the decline in l. pertusa.\nd. oxygenation in the alboran sea tended to be substantially higher than oxygenation near the mauritanian coast during the period studied.

Answer

Brief Explanations:

  • First, note that the ratio of manganese to calcium inversely correlates with ocean oxygenation levels (higher ratio = lower oxygenation).
  • For the Alboran Sea: The population of Lophelia pertusa declined around 9,000 years ago. Looking at the graph, there is a significant increase in the manganese - to - calcium ratio (which means a decline in oxygenation) around that time.
  • For the Mauritanian coast: The population of Lophelia pertusa declined around 11,000 years ago. The graph shows little change in the manganese - to - calcium ratio (so little change in oxygenation) around that time.

Answer:

B. L. pertusa declined in the Alboran Sea during a period of substantial local decline in oxygenation, but L. pertusa declined near the Mauritanian coast during a period of little local change in oxygenation.