As xiggi said, this question is far different from the “reasoning” taught in school math. I have met many kids who struggle through pre calc get much higher SAT math scores than the kids who aced AP calc. The SAT, imho, does a much better job of allowing kids with innate ability and true understanding of concepts to shine (as opposed to follow the procedure teacher taught me hacks). I’ve yet to encounter an ACT math question that made me think, “ah, of course! Cool!” Most SAT maths can be solved by just thinking about them… what is possible, what is not. School math rarely teaches this skill. And because the SAT actually tests that every once in a while, I think it’s a better test. I mean, colleges have school grades to tell how well a student can follow procedures and memorize formulas.
Thanks JOD - I missed it earlier. Just I tend to miss words in my own post. 
(A) 14-20-13 — 13 is odd, 20 is a multiple of 5, 14 is his birthday, correct
(B) 14-25-23 — 25 is odd and a multiple of 5, wrong
© 15-18-16 — 15 is odd and a multiple of 5, wrong
(D) 20-15-20 — 15 is odd and a multiple of 5, wrong
(E) 34-30-21 — 34 isn’t odd, a multiple of 5, or a day of the month, wrong
Okay so I know the best answer is (A) but I do agree with people who think that this question is not worded in a proper way. I will tell you why.
The question specifically states that EACH NUMBER SATISFIES EXACTLY ONE OF THE CONDITIONS. This means that a number given cannot satisfy multiple conditions. Taking this into consideration, let’s look at the numbers listed in choice (A) which are 14-20-13.
14 satisfies one condition only (ONE NUMBER IS THE DAY OF THE MONTH) which is good so far.
20, however, satisfies TWO conditions which are ONE NUMBER IS A MULTIPLE OF 5 and ONE NUMBER IS THE DAY OF THE MONTH. Such fact contradicts the question itself which said EACH NUMBER SATISFIES EXACTLY ONE OF THE CONDITIONS.
13 also satisfies TWO conditions which are ONE NUMBER IS ODD and ONE NUMBER IS THE DAY OF THE MONTH.
All other choices make more explicitly as to why those are not the answers but I do think that choice (A) in itself is also flawed.
Not the best question
Not sure how you are reading this. If in fact he was born on the 14th, then every # in choice A satisfies exactly one of the requirements. So A is a potential answer. But there is no day of the month when he was born that would let you say that about any of the other answer choices.
My hunch is that questions like this are not going to be part of the new SAT. Here are two others that I’m guessing we have seen the last of:
How many of the first 100 positive integers contain the digit 7?
And the one about drawing socks from a draw with blue, brown, black, and white socks…how many do you need to draw out to be sure of having a matching pair?
I’ll be sorry to see this element of thinking/playing de-emphasized on the test. Real math is in fact a playful puzzle. For some students, SAT prep is the first time that they are exposed to that aspect of mathematics!