**Core Concept**
Paralytic squint, also known as paralytic strabismus, occurs when there is weakness or paralysis of one or more extraocular muscles, leading to misalignment of the eyes (strabismus). This can result in diplopia (double vision) and squint.

**Why the Correct Answer is Right**
In this case, the patient's symptoms of diplopia and squint, with secondary deviation being greater than primary deviation, are characteristic of paralytic squint. When a patient with paralytic squint looks in the direction of the affected muscle, the affected eye is unable to move as far as the unaffected eye, resulting in the greater secondary deviation. This is because the affected muscle is weakened or paralyzed, preventing it from contributing to the eye movement.

**Why Each Wrong Option is Incorrect**
**Option A:** Restrictive squint is a condition where there is mechanical restriction of eye movement due to a pathological process, such as a tumor or a surgical scar, but it does not involve paralysis of the extraocular muscles.

**Option B:** Incomitant squint refers to a type of strabismus where the angle of deviation changes with gaze direction, but it does not necessarily involve paralysis of the extraocular muscles.

**Option C:** Pseudo squint is a condition where the eyes appear to be misaligned due to a pathological process, such as a cranial nerve palsy, but it does not involve paralysis of the extraocular muscles.

**Clinical Pearl / High-Yield Fact**
Key clinical features of paralytic squint include diplopia, squint, and a greater secondary deviation than primary deviation. In addition, patients with paralytic squint may exhibit a characteristic "A" pattern of strabismus, where the affected eye turns inward (esotropic) and the unaffected eye turns outward (exotropic).

**Correct Answer:**
✓ Correct Answer: A. Paralytic squint