<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 15-month-old girl is brought to the physician because of the sudden appearance of a rash on her trunk that started 6 hours ago and subsequently spread to her extremities. Four days ago, she was taken to the emergency department because of a high fever and vomiting. She was treated with acetaminophen and discharged the next day. The fever persisted for several days and abated just prior to appearance of the rash. Physical examination shows a rose-colored, blanching, maculopapular rash, and postauricular lymphadenopathy. Which of the following is the most likely diagnosis?? A: Nonbullous impetigo, B: Roseola infantum, C: Drug allergy, D: Rubella, E: Erythema infectiosum,  <response>: This is a clinical vignette describing a 15-month-old girl with a sudden onset rash after having a recent fever and vomiting. The key findings are:- 15-month-old girl - Sudden appearance of a rose-colored, blanching, maculopapular rash on trunk that spread to extremities - Rash started 6 hours ago- 4 days ago, went to ED for high fever and vomiting, was treated with acetaminophen- Fever persisted for several days before abating just prior to rash- Physical exam showed postauricular lymphadenopathyBased on the description, the most likely diagnosis is roseola infantum choice B. Roseola infantum classically presents with several days of high fever followed by the sudden appearance of a morbilliform rash as the fever resolves. The rash starts on the trunk and spreads outward. Postauricular lymphadenopathy is also characteristic. Choices A, C, D, and E can be ruled out based on the clinical presentation. Nonbullous impetigo, drug allergy, and rubella would not have the classic fever then rash presentation. Erythema infectiosum also presents differently, with a slapped cheek rash followed by a lace-like rash on extremities.B: Roseola infantum 