One of the example of decision structure is “if” statement.

Hence, the correct answer is option “B”.

Decision structure:

Sequence structure cannot handle all types of tasks. These can be achieved using decision structure. Example: “if” statement.

“if” statement:

“if” statement is used to make a decision structure, which permits the program to hold more than one path of execution.

• The indented statement is executed only when the condition is “true”.
• If the given condition is “false”, it skips the indented statements.

Syntax for “if” statement:

if condition:

indented_statement_block

Explanation for incorrect options:

Sequence Structure:

Simplest form of control structure is the “sequence structure”. It is a group of statements that are executed in the order in which they appear.

Hence, the option “A” is wrong.

Pathway Structure:

Pathway structure does not execute the statements under certain conditions.

Hence, the option “C” is wrong.

Class Structure:

Class structure is defined as a hierarchical organization where a community is divided into classes.

Hence, the option “D” is wrong.