首页
登录
职称英语
The most popular organic gem is the pearl. A pearl is the response of a mari
The most popular organic gem is the pearl. A pearl is the response of a mari
游客
2025-02-03
47
管理
问题
The most popular organic gem is the pearl. A pearl is the response of a marine mollusk to the presence of an irritating impurity accidentally introduced into its body; a cultured pearl is the result of the intentional insertion of a mother-of-pearl bead into a live mollusk. Whether introduced accidentally or intentionally, the pearl-making process is the same: the mollusk coats the irritant with a substance called nacre. Nacre is composed chiefly of calcium carbonate. Because very few natural pearls are now on the market, most pearls used in fine jewelry are cultured. These include "Biwa" pearls and most other freshwater pearls. Cultured pearls are not easily distinguished from natural pearls except by an expert. [br] The main idea in this passage is that ______
选项
A、most marketable pearls are cultured because nature does not produce enough of its own to satisfy the market
B、cultured pearls are of a higher quality than natural pearls
C、there are two major methods of pearl-making
D、a natural "drought" of pearl production is taking place
答案
C
解析
阅读全文可知本文介绍了珍珠有天然和人工养殖两种形成方式;所以选项C正确。
转载请注明原文地址:https://tihaiku.com/zcyy/3940802.html
相关试题推荐
Themostpopularorganicgemisthepearl.Apearlistheresponseofamari
Themostpopularorganicgemisthepearl.Apearlistheresponseofamari
Themostpopularorganicgemisthepearl.Apearlistheresponseofamari
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
随机试题
SQUALID:A、immaculateB、irrelevantC、ornateD、plentifulE、tepidA
______succeedindoinganything.A、OnlybyworkinghardwecanB、Byonlyworking
HowlongwillthecoolingoffperiodbeaccordingtotheagreementbetweenIsrae
中班游戏活动《勇敢的小兔子》
在具有长期趋势的时间序列中,通常认为这种长期趋势是由各种固定的因素作用于某一方面
A.喹诺酮类 B.青霉素 C.阿苯达唑 D.四环素 E.补充液体及电解质
高钙血症导致A.高镁血症 B.尿镁降低 C.尿镁增加 D.高磷血症 E.
拆迁当事人向原估价机构申请复核估价的,该估价机构应当自收到书面复核估价申请之日起
搞好劳动定员工作的核心是()A:定员数量的高低宽紧程度适中 B:既保证生产的需
甲与乙婚后购买一套房屋,产权证载明所有权人为乙。后双方协议离婚,约定房屋赠与女儿
最新回复
(
0
)