This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to make simple hard cider
The must is the mixture of ingredients you mix prior to the fermentation that will eventually become your cider.
Take your 2 liter (0.5 us gal) soda bottle and fill it with 250 ml of carton apple juice and 1 liter (0.3 us gal) of water.
Mix in your sugar.

Pick your answer from:
[a]. Sugar is used to boost the metabolism of the yeast and increase the alcohol content. It is best to use your own judgement as per how much of each to add as long as they're both completely dissolved.
[b]. Use leftover ice from previous fermentation for most of this. Consider adding ground sweetener to the mixture.
[c]. What you've got is gallon (1.9 us gal) of sugar for every 5 us gallons of water in your jar. Make sure the sugar is enough so that it turns out smooth and creamy.
[d]. Add the mint and lime juice and stir. Strain into a fine-mesh sieve.
The answer is:
[a].