Section A
　　Directions：In this section,there is a passage with ten blanks．You are required to select one word for each blank from a list of choices given in a word bankfollowing the passage．Read the passage through carefully before making your choices．Each choice in the bank is identified by a letter．Please mark the corresponding lette for each item on Answer Sheet 2 with a single line through the centre．You may not use any ofthe words in the bank more than once． 

　　Questions 36 to 45 are based on the following passage.
　　Climate change has claimed its latest victim：Limacina helicina，a planktonic，predatory(捕食的)sea snail that’s a member of the taxonomic group more(36)__________ known as sea butterflies．(The name is(37)__________ from the wing-like lobes(葉瓣)the tiny creatures use to get around．)In a study(38)__________ published in joumal Proceedings of the Royal Society B，a group of scientists from the National Oceanic and Atmospheric Administration (NOAA)and Oregon State University have fQund that the Pacific Ocean’s decreasing pH—its acidifying(酸化)，in other words-is dissolving L．helicina’s thin shells．
　　The researchers collected sea butterfly(39)__________ from 13 sites along the Pacific coast(between Washington and southern CaliforniA.，going over each with a scanning electron microscope．More than half of the shells(53％)from onshore individuals(40)__________ signs of“severe dissolution damage，”while 24％of(41)
__________ individuals suffered dissolution damage．The study’s(42)__________ investigator,Dr．NinaBednarsek of NOAA，described the affected L．helicina shells as having a texture not unlike“cauliflower”or“sandpaper．”
　　According to the paper，there was a“strong positive(43)__________ ”between the proportion of sea butterflies with severe shell dissolution damage and“the percentage of　undersaturated(未達(dá)到飽和的)water”near the ocean’s surface．The researchers conclude“shell dissolution owing to(human．caused ocean(44)_________has doubled in near shore habitats since pre．industrial conditions across this region and is on track to triple by 2050，”a truly(45)__________ prediction．Moreover,the broader implications for ecosystem are unclear,as damaged shells make it harder for L．helicina to fight infections，stay buoyant，and protect themselves from predators．

A.showed
B.recently
C.protected
D.commonly
E.derived
F.samples
G.offshore
H.principal
I.noticed
J.correlation
K.encouraging
L.seaward
M.acidification
N.grim
O.pollution

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