Name a hormone which
A.is gaseous in nature
B. is responsible for phototropism
C. induces femaleness in flowers of cucumber
D. is used for killing weeds (dicots)
E. induces flowsering in long day plants

Explanation

To answer the question, we will break it down into its components and identify the appropriate hormone for each part.

### Step-by-Step Solution:

1. **Identify a hormone that is gaseous in nature:**
- The hormone that is gaseous in nature is **ethylene**. Ethylene is known for its role in various plant processes, including fruit ripening and response to stress.

**Hint:** Think about the role of ethylene in fruit ripening and how it is released as a gas.
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