Least common site involvement in psoriasis is –: (A) Scalp, (B) Nail involvement, (C) CNS involvement, (D) Arthritis
Answer is C. Not found in psoriasis

Alopecia (despite the involvement of scalp)
Face involvement (though scalp lesion can extend on forehead
Mucosal involvement

Uncommon in psoriasis

Joint involvement (5-10%)
Pruritis