Despite being in the career of singing for the last ten years, he has not been able to earn fame on account of his practice of borrowing ideas and words from others and using them as his own.

Answer: Option D

One word substitute is Plagiarism.

Adaptation: the action or process of adapting or being adapted.
Pantomime: a theatrical entertainment, mainly for children, which involves music, topical jokes, and slapstick comedy and is based on a fairy tale or nursery story, usually produced around Christmas.
Imitation: the action of using someone or something as a model.
Plagiarism: submitting someone's work as their own.