If, in a tennis tournament, a match reaches a fifth-set tiebreak, the

OFFICIAL EXPLANATION

On a "mimic the argument" question, it's useful to use logic notation to understand the flow of the argument. In this case, we're told that IF A happens (a match reaches a fifth-set tiebreak), THEN B will definitely happen (the lower-ranked player loses). Standard logic rules tell us that, when given "If A, then B," the only definite conclusion we can draw is "If not B, then not A." In other words, if A always leads to B, and B doesn't happen, then A can't have happened either. The second sentence of the argument shows this principle: If not B (the lower-ranked player doesn't lose), then not A (there wasn't a fifth-set tiebreak). So we need to find another argument that follows this pattern: If A, then B; if not B, then not A.

(A) CORRECT. If A (a woman with a family history of twins gets pregnant 3 times), then B (she will have 1 set of twins). Note that these numbers are precise: if she gets pregnant exactly three times, she will have exactly one set of twins. If not B (a woman with a family history of twins has 2 sets of twins - that is, not 1), then not A (she must have gotten pregnant either fewer than 3 times or more than 3 times - that is, not exactly 3 times).

(B) If A (a salesman sells more product than anyone else), then B (he will earn an all-expenses-paid vacation). If B (Joe earned the trip), then A (he must have sold more than anyone else). We can see why logic rules do not include "if B, then A" as a logical conclusion: A may always lead to B, but B does not necessarily have to lead to A. There may be other ways to earn the trip besides selling more than anyone else.

(C) If A (a newspaper's circulation surpasses 100,000), then B (the newspaper can charge a 50% premium). If not A (the circulation doesn't surpass 100,000), then not C (the newspaper cannot charge any premium). The final assertion here does not match the initial A / B argument We know nothing about any other premium the newspaper might charge; we are only given information about charging a 50% premium.

(D) If A (a student is in the top 10% of the class), then B (she will earn a scholarship). If not A (Anna is not in the top 10%), then not B (she won't earn a scholarship). We can see why logic rules do not include "if not A, then not B" as a logical conclusion: A may always lead to B, but it doesn't have to be the only way to reach B. There may be other ways to earn a scholarship besides being in the top 10% of the class.

(E) If A (the team wins the Super Bowl), then B (the players receive a bonus). If not A (a player was not on the winning team), then not B (the player won't receive a bonus). We can see why logic rules do not include "if not A, then not B" as a logical conclusion: A may always lead to B, but it doesn't have to be the only way to reach B. There may be other ways to earn a bonus besides winning the Super Bowl.

+1 A

Notice tha there is a flaw in the reasoning of the original argument:
The statistics of the past will determine what will happen in the future. But we know that that's not true.
The rest of the arguments don't have that flaw. Most of them have a cause-effect argument.

If A --> B

If Not B --> Not A

On the same line, If a woman with a family history of twins gets pregnant three times -- A
she will have one set of twins -- B

Jennifer had two sets of twins -- Not B

so she must not have gotten pregnant exactly three times -- Not A

Hence, Answer is A

Can anyone please help here.
Why not B ?

Also can someone throw light on Method of reasoning & how to solve it in the given timeframe.
Any links or notes will be highly useful.

In B, we have the form If A --> Then B in the first rule.

Then the example says If B--> Then A. Which may or may not be true. Hence , it is incorrect.

This question is something like: If X then Y. If not Y then not X.....

That is, if we look at the question, then the format is:-

Premise (P): If X then Y.
Conclusion (C): If not Y then not X.

Now formulate the same things for the options also.

A)
Premise (P):If X then Y.
Conclusion (C): If not Y then not X.
(This match the original pattern, hence should be the correct answer).

B)
Premise (P):If X then Y.
Conclusion (C): Y then X. (Wrong, it does not match the pattern).

C)
Premise (P): X then Y. (Wrong, does not match the pattern).
Conclusion (C): If not Y then not X.

D)
Premise (P): If X then Y.
Conclusion (C): If not X then not Y
(Wrong, does not match the original pattern).

E)
Premise (P): X if Y
Conclusion (C): Y then X
(Wrong, does not match the original pattern).

Highly tricky one it was a magnetic field repulsion between A and E however as A pointed out a reason supporting from the premise of the reason and denial of the same from the argument , this was more than enough as E didn't contain all of these designated attributes hence IMO A

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