The word "butter" is an uncountable noun, so we use "little" to indicate a small amount.
"Some" is used when referring to an additional quantity.
The correct sentence should be:
"There is little butter left, but you can have some."
Thus, the correct answer is "little, some" (Option B).
Arun’s present age in years is 40% of Barun’s. In another few years, Arun’s age will be half of Barun’s. By what percentage will Barun’s age increase during this period?