यदि परवलय \(y^{2}=4 x\) की नाभिलम्ब जीवा, दो वृत्तों, \(C_{1}\) तथा \(C _{2}\) की उभयनिष्ठ जीवा है, जबकि वृत्तों में से प्रत्येक का अर्धव्यास \(2 \sqrt{5}\) है, तो वृत्तों \(C _{1}\) एवं \(C _{2}\) के केन्द्र बिन्दुओं के बीच की दूरी है 

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.