Which of the following is not possible directly in nitrobenzene?

Options

A. Halogenation
B. Sulphonation
C. Nitration
D. Alkylation

Explanation

To solve the question "Which of the following is not possible directly in nitrobenzene?", we need to analyze the reactivity of nitrobenzene in various chemical reactions, particularly focusing on Friedel-Crafts reactions.

### Step-by-Step Solution:

1. **Understanding Nitrobenzene**: Nitrobenzene is a benzene ring with a nitro group (-NO2) attached to it. The presence of the nitro group significantly affects the reactivity of the benzene ring.

2. **Friedel-Crafts Reactions**: Friedel-Crafts reactions include two main types: alkylation and acylation. These reactions involve the introduction of alkyl or acyl groups onto the benzene ring using electrophiles.

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