In the world of SQL relational database, the data type of integer, in general, is

A.
16-bit signed integer

B.
32-bit signed integer

C.
Signed decimal number, p digits, q decimals

D.
Floating point number of p bits precision

E.
Fixed length string of n characters

F.
Variable length string up to n characters

Explanation:
Memorize this list SMALLINT 16-bit signed integer
INTEGER 32-bit signed integer
DECIMAL(p,q. Signed decimal number, p digits, q decimals
FLOAT(p. Floating point number of p bits precision
CHAR Fixed length string of n characters
VARCHAR(n. Variable length string up to n characters
DATE Date ( in the form yyyymmmmdd.
TIME Time (in the form hhmmss.
TIMESTAMP Combines a DATE and a TIME