Question

The least number of squares to be added in the figure to make AB a line of symmetry is: 

• A. 6
• B. 4
• C. 5
• D. 7

Hint:

When checking symmetry, match squares across the axis line. Count how many additions are required to mirror all shapes exactly.

Answer 1

The Correct Option is B

Step 1: Identify symmetry axis.
The line AB is a horizontal line across the middle. For the figure to have symmetry, each square above AB must be matched by one below AB, and vice versa.
Step 2: Count missing counterparts.
- On the left: one square above AB, but two squares below AB (1 missing above to balance).
- On the right: one square below AB, but none above AB (1 missing above to balance).
- Center: extra imbalance requires two more squares (one above, one below).
Step 3: Total required.
Adding these missing squares: \(4\).
\(\boxed{4}\)