Hi, Claudia,
Thanks for your question and welcome to the forum!
This Must Be True question is an example of the more formal, deductive logic that comprises a subset of the Argument (LR) problems and more-or-less all of the Games (AR) problems. In other words, this kind of question requires extraordinary precision. However, you need not feel intimidated. You solved this problem correctly through process of elimination, which often presents the most expeditious path to the solution.
Let's break down this process of elimination process for Must Be True (MBT) problems. Essentially:
- Assess the information in the stimulus to ascertain what facts are known.
- Notice any connections between these facts to get an idea of any possible inferences.
- For each answer choice, ask yourself, "Do I know this to be true for sure?"
As you saw, the only answer we knew to be true for sure was (B). Alternately, you might notice that for the rest of the answers you might have responded, "Maybe... could be true. I'm not sure." Any answer for an MBT problem that prompts you to scratch your chin and go "maybe..." is an incorrect answer.
Now let's go through a formal explanation of the reasoning here:
- Successful GD Years of Formal Training (This just means "there exists a successful graphic designer such that this successful graphic designer started her career after years of formal training.")
- Successful GD NOT Years of Formal Training (Notice this "informally on the job" just means "NOT years of formal training, in other words "there exists a successful graphic designer such that this successful graphic designer started her career NOT after years of formal training."
- Successful GD NOT ignore wishes of a client (This last statement is a conditional, an "if...then" statement. It can be given like this or as its contrapositive: Ignore wishes of a client NOT successful GD)
Now ask yourself what you know for sure. Try to make a connection between at least two of the statements. There is no evident connection between statements (1) and (2). Those two just say, "Some successful graphic designers got formal education. Some didn't."
However, try to make a connection either between statements (1) and (3) or between statements (2) and (3). Between these what can we surmise? We know:
- All successful graphic designers don't ignore their clients' wishes (3). Thus, some graphic designers who got a formal education (the successful ones) do not ignore their clients' wishes (combining (1) and (3)). Otherwise, they wouldn't be successful!
Alternatively, some graphic designers who learned informally on the job (the successful ones) do not ignore their clients' wishes (combining (2) and (3)). Otherwise, they wouldn't be successful!
These are the two possible
prephrases for these statements, the first of which matches Answer Choice (B). I hope this helps! Please follow up with further questions!