Choose the option to fill in the blank in the sentence given below.
Heard melodies are sweet ____ those unheard are sweeter.

Correct option is A

Correct option: (a) yet
Meaning & usage (in detail):
• yet = but/however; shows contrast between two ideas (Hindi: फिर भी / लेकिन)
• Sentence meaning: Heard melodies are sweet, but unheard melodies are even sweeter.
Correct sentence: Heard melodies are sweet yet those unheard are sweeter.
Grammatical rule (English):
• yet is a coordinating conjunction used to show contrast, similar to but.
व्याकरणिक नियम (Hindi):
• “yet” एक conjunction है जो विरोध/contrast दिखाता है (but की तरह)।
Meanings of other options (in detail):
• (b) but → लेकिन (contrast) (possible in meaning, but the given famous line commonly uses “yet”; exam key expects “yet”).
• (c) and → और (addition; contrast नहीं)
• (d) for → क्योंकि/क्योंकि (reason; contrast नहीं)
Hence, option (a) is the correct answer.