Pseudo koebener’s phenomeneon is/are seen in – a. Warts b. Molluscum contagiosum c. Lichen planus d. Psoriasis

**Core Concept**
Pseudo-Köbner's phenomenon, also known as isomorphic response or Koebnerization, refers to the development of skin lesions on lines of trauma or injury in individuals with certain skin conditions. This phenomenon is characterized by the appearance of new lesions at the site of skin trauma, which can occur in various dermatological conditions.

**Why the Correct Answer is Right**
The correct answer is seen in Molluscum contagiosum, a viral skin infection caused by the molluscum contagiosum virus (MCV). The phenomenon occurs due to the reactivation of the virus at the site of skin trauma, leading to the formation of new lesions. This is thought to be mediated by the immune response, which can be triggered by skin injury.

**Why Each Wrong Option is Incorrect**
* **Option A:** Warts are caused by human papillomavirus (HPV) and do not typically exhibit pseudo-Köbner's phenomenon.
* **Option C:** Lichen planus is an autoimmune condition characterized by inflammation of the skin and mucous membranes, but it is not typically associated with pseudo-Köbner's phenomenon.
* **Option D:** Psoriasis is a chronic autoimmune skin condition characterized by thickened, scaly skin lesions, but it is not typically associated with pseudo-Köbner's phenomenon.

**Clinical Pearl / High-Yield Fact**
Pseudo-Köbner's phenomenon is a useful clinical sign that can help diagnose conditions such as molluscum contagiosum, especially in children. It is essential to recognize this phenomenon to avoid misdiagnosing skin lesions.

**Correct Answer:** B. Molluscum contagiosum.