Okay this is a simple question for States of Matter chapter of Inorganic Chemistry.

32 g of oxygen contains 22.4 litre's or 22400 cm3
now 6.4. g contains 22.4 X 0.2= 4.48 litre or 4480 cm³ or ml

Practice more such simple and complicated mcqs specially if you preparing for national level competitive entrance examinations.

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https://medicine.careers360.com/articles/how-study-chemistry-for-neet

https://engineering.careers360.com/articles/jee-main-preparation-tips-for-chemistry

Best wishes. Thank you.