Geometry

Question Analysis
This question involves identifying the correctly written biconditional statement.
The main focus is on verifying the logical validity of each statement.

Key Concept Explanation:
A biconditional statement requires both the original statement and its converse to be true, linked by "if and only if."

Step-by-Step Solution:
Analyze each option to determine if both the original statement and its converse are true.

Option A:
Original: If a polygon is a pentagon, then it has five sides. (True)
Converse: If a polygon has five sides, then it is a pentagon. (True)
This is a valid biconditional statement.

Option B:
Original: If a shape is a rectangle, then it has opposite sides that are equal. (True)
Converse: If a shape has opposite sides that are equal, then it is a rectangle. (False, it could be a parallelogram or rhombus)
This is not a valid biconditional statement.

Option C:
Original: If a number is prime, then it is odd. (False, 2 is prime but not odd)
Converse: If a number is odd, then it is prime. (False, 9 is odd but ...