**Core Concept**
Nodulocystic acne is a severe form of acne characterized by large, painful nodules and cysts on the skin. It is a chronic inflammatory condition that requires aggressive treatment to prevent scarring.

**Why the Correct Answer is Right**
The treatment of choice for nodulocystic acne is isotretinoin, a synthetic retinoid that works by reducing the size and activity of the oil glands in the skin. Isotretinoin inhibits the synthesis of sebum, which is a key factor in the development of acne. It also has anti-inflammatory properties that help to reduce the size and redness of acne lesions. Isotretinoin is effective in treating nodulocystic acne because it targets the underlying cause of the condition and prevents the formation of new lesions.

**Why Each Wrong Option is Incorrect**
**Option A:** Topical retinoids, such as adapalene and tretinoin, are effective in treating mild to moderate acne but are not sufficient to treat severe nodulocystic acne. They work by promoting cell turnover and preventing clogged pores but do not address the underlying inflammatory process.

**Option B:** Oral antibiotics, such as doxycycline and minocycline, are sometimes used to treat acne by reducing inflammation and killing bacteria that contribute to the development of acne. However, they are not effective in treating severe nodulocystic acne and may not address the underlying cause of the condition.

**Option C:** Benzoyl peroxide is a topical antibiotic that is effective in treating mild to moderate acne by killing bacteria that contribute to the development of acne. However, it is not sufficient to treat severe nodulocystic acne and may not address the underlying inflammatory process.

**Clinical Pearl / High-Yield Fact**
Isotretinoin is a highly effective treatment for nodulocystic acne but requires careful monitoring due to potential side effects, including dry skin, joint pain, and increased risk of depression.

**Correct Answer: C. Benzoyl peroxide**