Four samples of natural water from different sources are taken in four petri dishes in equal quantities. These are marked as A, B, C, D and kept in an oven till the entire water vaporizes. When they were taken out, it is observed that sample marked 'C' left maximum amount of residue while sample marked 'B' left negligible amount of residue. 'A' and 'D' left almost same amount of residue.
Identify B and C

Explanation

To solve the question, we need to analyze the information given about the four samples of water (A, B, C, D) after they have been evaporated in an oven.

### Step-by-Step Solution:

1. **Understanding the Experiment**: We have four samples of natural water from different sources (A, B, C, D) placed in petri dishes. They are heated until all the water evaporates, leaving behind any dissolved substances as residue.

2. **Observing Residue**: After evaporation, we note the amount of residue left:
- Sample C left the maximum amount of residue.
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