IB chem ideal gases question

answer is D
can someone explain? for some reason the numbers I found are not matching up


the question is meant to confuse you in the units
the question is not in SI units at all, instead of converting them, we need to cancel them out
PV=nRT so PV=n/Mw RT so Mw=(mRT)/PV

R is given in cm³ atm K⁻¹ mol⁻¹, and we need Mw to be in g/mol
we need to cancel the units cm³ atm K⁻¹ by not converting anything except temperture from celsius to kelvin (35+273=308°K)

Mw=(1,42 * 82,05 * 308)/(250 * 0,85)
Mw=(g cm³ atm K⁻¹ mol⁻¹ K)/(cm³ atm) = g * mol⁻¹ the units are now balanced