Final answer:
The word that matches the meaning of "use" is a) utilize, as it means to make practical and effective use of something.
Step-by-step explanation:
Among the options provided, the word that matches the meaning of "use", which is to employ something, is a) utilize. Utilize means to make practical and effective use of something. This is in contrast to the other options: b) waste, which means to use carelessly or without necessary purpose; c) ignore, which means not to acknowledge or use at all; and d) reserve, which refers to keeping something back or saving it for future use or a special purpose.