Examine this statement, which execut

单选题

Examine this statement, which executes successfully:

CREATE TABLE world.city (

ID int NOT NULL AUTO INCREMENT,

Name char(35) NOT NULL DEFAULT ",

CountryCode char(3) NOT NULL DEFAULT ",

District char(20) NOT NULL DEFAULT ",

Population int NOT NULL DEFAULT '0',

PRIMARY KEY (ID),

KEY CountryCode (CountryCode)

) ENGINE=InnoDB;

You want to improve the performance of this query:

SELECT Name

FROM world.city

WHERE Population BETWEEN 1000000 AND 2000000;

Which change enables the query to succeed while accessing fewer rows?

A、

ALTER TABLE world.city ADD SPATIAL INDEX (Name);

B、

ALTER TABLE world.city ADD SPATIAL INDEX (Population);

C、

ALTER TABLE world.city ADD INDEX (Population);

D、

ALTER TABLE world.city ADD INDEX (Name);

E、 ALTER TABLE world.city ADD FULLTEXT INDEX (Name);

F、 ALTER TABLE world.city ADD FULLTEXT INDEX (Population);

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