Consider the following EXPLAIN output.

mysql> EXPLAIN SELECT Name FROM City WHERE Population > 8000000
*************************** 1. row ***************************
id: 1
select_type: SIMPLE
table: City
type: ALL
possible_keys: NULL
key: NULL
key_len: NULL
ref: NULL
rows: 4079
Extra: Using where
Which of the following statements are true?
A. The query cannot be optimized any better.
B. No index could be used to perform the query.
C. All 4079 rows of the table need to examined.
D. The Name column should be indexed.
E. The Population column should be indexed.

Answer: BCE

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