Deficiency of which vitamin causes the following diseases :
(1) Scurvy
(2) Night blindness.

Explanation

To solve the question regarding the deficiency of vitamins that cause specific diseases, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Identify the first disease**: The first disease mentioned is **scurvy**.

- **Research the cause**: Scurvy is characterized by symptoms such as bleeding gums, fatigue, and weakness. It is a condition that arises due to a deficiency in a specific vitamin.

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