You will be given a definition of a task first, then some input of the task.
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". 

[header] How to buy ram for your imac [title] Buy no more than 16 gb of extra ram. [step] Imacs from 2011 , 2010, and late 2009 support a total of 16 gb of memory. [substeps] You can buy up to 4 different rams, or memory modules, for these imac models; however, they must not exceed a total of 16 gb in memory. <sep> (A) [title] Buy ram with features that are compatible with your imac model. [step] Imac models from 2011 and 2010 use the same type of ram; whereas the late 2009 models use ram with slightly different features. (B) That means a lcd ram is capable of that ram. You'll need at least 2 gb of ram/ram per ram. (C) You will want to buy between 120 gb to 30 gb. Most drivers come with two gigabytes of ram. (D) [title] Learn how pcp to own your pc. [step] Pcp (bce/100 gb) is the unit used in most computers of throughout the world for the main battery, typically, memory modules.
Output:
A