A popular model of constructing an argument that makes its appearance in GMAT every now and then is known as the cause and effect Model. The premise of this argument model typically consists of two events happening simultaneously. Lets identify these two events as X and Y respectively . The author of the argument establishes a causation between these two events by stating that One(say X) causes the Other( Y).
When the author puts forth this argument he invariably takes three different assumptions. One of these assumptions is , ” There is no alternate cause of the Event Y”. This means he takes it for granted that the one and only cause of the event Y is the event X.
The knowledge of this assumption inherent in the cause and effect argument model can help the test taker in answering as many as three different question types asked for arguments based on this model. They are Assumption, Weakening & Strengthening.
Now, Let’s see how this assumption can be utilized to answer assumption questions based upon this Model.Because ‘There is no alternate cause of the Event Y’ has been identified as an assumption hidden in the given Argument, the correct option for assumption questions pertaining to this model will highlight a possible alternate cause for the Event Y and then will negate the possible alternate cause by stating that it was absent at the time when event Y occurred. This is how this assumption is utilized to answer assumption questions of the argument. The usage of this assumption for the strengthening questions is no different. The moment a possible alternate cause is negated by a given Answer choice that Answer choice serves to strengthen the causation established by the author in the argument and therefore, in turn, becomes the correct answer choice for the strengthening question posed upon the given argument.
For answering weakening questions based on the cause and effect model of the argument, the assumption, ‘There is no alternate cause for the event Y’ is weakened by highlighting another possible cause of the event Y.
Hence, The above discussion makes it clear that “The Alternate Cause” in itself is neither a weakener nor a strengthener. But it can be utilized to play either one of the roles.