In this item, there needs to be a basis as to how many significant numbers can be present in a certain figure. If the answer 327.66 m/s is to be expressed as a 3 significant figures only, the answer would have to be 328. What was done here is to simply round up the units digit of the number since the decimal place (tenths) digit has a value of greater than 4.
The answer to this item is therefore letter B.
