Which of the following capital letters of the English alphabet possesses **both** horizontal and vertical line symmetry (reflectional symmetry)?

(A) H

(B) A

(C) B

(D) E

Answer Key:

Verified in official key

### 1. Strategy & Theoretical Principles - **Vertical symmetry axis:** Reflection across the vertical midline maps the left half onto the right half (e.g., A, M, T, V, W, Y). - **Horizontal symmetry axis:** Reflection across the horizontal midline maps the top half onto the bottom half (e.g., B, C, D, E, K). - **Both axes of symmetry:** Letters invariant under both reflections (as well as $180^\circ$ point rotational symmetry) are: **H, I, O, X**. ### 2. Analytical Evaluation - **H:** Has a vertical axis of symmetry through its center, and a horizontal axis of symmetry through its crossbar. Invariant under both. - **A:** Only vertical symmetry. - **B:** Only horizontal symmetry. - **E:** Only horizontal symmetry. ### 3. Distractor Forensics - Only **H** satisfies both horizontal and vertical line reflection requirements. ### 4. Exam Trap & Standard Reference - **Trap Alert:** Remember the dual-symmetric set of standard sans-serif capital letters: {H, I, O, X}. - **Standard Reference:** GATE General Aptitude Official Syllabus - Spatial Aptitude.

← Prev Question Next Question →