Read the stanza given below and complete the sentences by choosing the appropriate option.

Day by day the nightingale
Grew more sorrowful and pale
Night on night her tired song
Zipped and trilled and bounced along,
Till the birds and beasts grew tired
At a voice so uninspired
And the ticket office gross
Crashed, and she grew more morose
For her ears were now addicted
To applause quite unrestricted,
And to sing into the night
All alone gave no delight.

The audience was tired of her song because…………………

(i) they had heard it many times

(ii) it had become mechanical

(iii) she looked tired

(iv) she had added trill to her song