In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D". 
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Question: [header] How to make black coffee [title] Purchase freshly roasted, whole bean coffee. [step] If you can't purchase it directly from the roaster within a week or so of it being roasted, opt for a vacuum-sealed bag from a reputable national coffee-bean roaster. [title] Purchase your own coffee grinder, or grind it in the store. <sep> (A) [step] If possible, choose a burr grinder in place of a normal blade grinder. For best results, grind the coffee fresh right before brewing each day. (B) [step] Grind coffee beans in the near-black zone of a coffee grinder. You can use either a regular-size grinder or a pre-grind grinder to grind your coffee. (C) [step] Modern coffee grinders have drawbacks, as they require higher temperatures to make purified coffee. Where possible, purchase one that comes pre-boil. (D) [step] Print it onto a piece of paper, remove the lid from the coffee grinder, and grind the coffee beans in the machine's center. [title] Unplug the coffee grinder and plug it into the wall outlet.

Answer: A


Question: [header] How to stop making excuses for toxic parents [title] Take a step back from your parents. [step] Get some space so you can gain perspective on your parent's behavior and your relationship with them. If you're around toxic or abusive behavior all the time, you may get used to it. <sep> (A) Give yourself a few minutes to breathe before jumping into a more draining conversation. [substeps] Take a moment to sort the information into fresh, concrete terms. (B) [substeps] Asking people to keep your distance can help you to find a second perspective. If you don't know what to say, ask questions. (C) Taking a break can help you get a clearer-eyed look at what's wrong. [substeps] If you still live with your parents, creating some distance can be tough. (D) Try to put yourself in their shoes, and see how you can make a change in yourself. [substeps] Just as many parents try their hand at parenting, they don't always resolve conflicts tactfully and maturely.

Answer: C


Question: [header] How to calculate a ph [title] Know what ph actually is. [step] The ph is the concentration of hydrogen ions in a solution. A solution with a high concentration of hydrogen ions is acidic. <sep> (A) A solution with a low amount of hydrogen ions is basic, or also known as alkaline. Hydrogen ions, also known as hydronium, are written shorthand as h or ho. (B) A solution with a lower concentration of hydrogen ions could produce a ph requiring constant testing. [substeps] One of the very most common ph disorders in medical terminology is macular degeneration. (C) Being aware of that fact can help you calculate the ph of your solution. [title] Create a ph chart to use for tracking the concentration. (D) A ph that is lower than zero may indicate a ph imbalance. A ph imbalance can be caused by both chemical reactions or a combination of both.

Answer:
A