We hope you have followed our detailed article on the Basics of Causal Arguments. Try solving this practice question on the concepts learned in the article and test your understanding of the same –

Question –

Reduced rainfall has been believed to cause production of low quality tea . A new report, noting that reduced rainfall and production of low quality tea are often observed to be preceded by pest attacks on the tea plants, suggests that pest attacks, not reduced rainfall, may be the cause of production of low quality tea.

Which of the following further observations would best support the new report’s suggestion?

A. In cases where pest attacks occur, followed by reduced rainfall, reduced rainfall is usually followed by production of low quality tea.

B. In cases where there is reduction in rainfall but no pest attack, reduction in rainfall is usually followed by production of low quality tea

C. In cases where there is reduction in rainfall but the quality of tea produced is not low, reduction in rainfall is usually preceded by pest attacks.

D. In cases where there is production of low quality tea, it is usually preceded by pest attacks and reduced rainfall.

E. In cases where pest attacks occur but there is no reduction in rainfall, the pest attack is usually followed by production of low quality tea.

Answer: E

Solution –

We hope you solved the question before scrolling! If not, let’s go back and solve it first!

Step 1 – Analyzing the stimulus and question stem

According to an earlier belief: Reduction in rainfall caused production of low quality tea.

According to a new report: Pest attacks have been observed to take place before both reduction in rainfall and production of low quality tea.

Conclusion: The new report suggests that pest attacks, not reduced rainfall, may be the cause of production of low quality tea

Step 2 – Pre-thinking

  1. The conclusion contains a cause and effect relationship, making this a causal argument. We have to strengthen the causality in the new report’s suggestion.
    • Cause: pest attacks – let this be X
    • Effect: production of low quality tea – let this be Y
      1. Not the cause: Reduced rainfall – let this be Z
  2. We can strengthen the above by using the following evidence:
    • Z did not cause Y
    • If X, then Y
    • No X, no Y
    • Y did not cause X

Step 3 – Answer Choice Elimination

Option A Analysis

This could mean that pest attacks cause reduced rainfall(illogical) and then reduced rainfall causes production of low quality tea. So in a way we are concluding Z causes Y and weakening the conclusion. We are to conclude that pest attacks, NOT reduced rainfall, causes production of low quality tea.

Incorrect Choice.

Option B Analysis

Per this choice reduction in rainfall (Z) causes production of low quality tea (Y). This weakens the conclusion.

Incorrect Choice.

Option C Analysis

Per this choice cause – pest attacks (X) is there, but no effect – no low quality tea (Y). This choice also weakens the conclusion.

Incorrect Choice.

Option D Analysis

Effect is present (low quality tea) and so are both causes. This choice neither supports nor weakens the conclusion. This choice is a distortion of given information.

Incorrect Choice.

Option E Analysis

Per this choice

  • When X occurs (pest attacks) but Z does not occur (no alternate cause)
  • Then X followed by Y

This choice works on two grounds:

  • If X, then Y
  • Z did not cause Y.

Correct Choice.