If the statement 'All plants are green organisms' is given as false, then which of the following statements could be immediately inferred to be true?

1.No plants are green organisms

2.Some green organisms are plants

3.Some plants are green organisms

4.Some plants are not green organisms

A1 only

B2 & 3 only

C1 & 4 only

D4 only ✓ Correct

Correct answer: (D) 4 only

Explanation

Only Statement 4, Some plants are not green organisms, is guaranteed true.

The given A proposition All plants are green organisms is declared false.

The contradictory of a false A is its O, which must therefore be true.

That O is exactly Statement 4, Some plants are not green organisms.

Statements 1, 2 and 3 are left undetermined, since a false A fixes only its contradictory.

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