Correct option is A
The correct answer is option
(a).
The word
‘impurities’ refers to substances that make something dirty or of lower quality. In the context of the passage,
impurities are the unwanted particles that are removed from the indigo paste during filtration.
Scum, which refers to a layer of dirt or froth on a liquid surface, closely aligns with this meaning as it represents unwanted or impure matter.
Other options are incorrect because:
•
(b) Pureness – means the state of being pure (शुद्धता), opposite of impurity.
•
(c) Cleanliness – refers to the quality of being clean (स्वच्छता), not a synonym of impurity.
•
(d) Purity – also means cleanliness or lack of contamination (निर्मलता), opposite in meaning.