The number of lines of symmetry in a protractor is
0
1
2
more than 2
What is a protractor?
A standard school protractor is a semicircle (half a circle) that measures angles from (0^circ) to (180^circ).
What is a line of symmetry?
A line of symmetry is a line that divides a shape into two equal mirror halves. If you fold the shape on this line, both parts match exactly.
Find the symmetry of a semicircular protractor
Look at the midpoint at the bottom (the center mark where you place the protractor). Draw an imaginary line going straight up through this midpoint.
This is a vertical line that cuts the semicircle into two equal halves.
Check by folding: If you fold the protractor along this vertical line, the left half sits exactly on the right half.
So this vertical line is a line of symmetry.
Why not other lines?
Horizontal line (along the straight edge):
Above the line there is a curved semicircle. Below the line there is nothing (no curve). They can’t match. So it is not a line of symmetry.
Slanted/diagonal lines:
These would make the left and right parts unequal, so they also fail the mirror test.
Conclusion:
The semicircular protractor has exactly (1) line of symmetry — the vertical line through its midpoint.
Correct Option: (1) → Option B