Valmiki Ramayana Ayodhya Kanda Sarga 82 Shloka 12
Original Shlokaकथं दशरथाज्जातो भवेद्राज्यापहारकः। राज्यं चाहं च रामस्य धर्मं वक्तुमिहार्हसि।।2.82.12।।
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दशरथात् from Dasaratha, जातः born, राज्यापहारकः usurper of the kingdom, कथम् भवेत् how will he become?, राज्यं च kingdom, अहं च I also, रामस्य belong to Rama, इह in this matter, धर्मम् truth, वक्तुम् to tell, अर्हसि it behoves you.
How can any usurper of the kingdom be born of Dasaratha? Or, how would any progeny of Dasaratha become the usurper of the kingdom? I and the kingdom, both belong to Rama. You should tell the truth about this.