If it is established as a true fact that "No certified organic pesticide is chemically synthetic", which of the following statements must be FALSE?
Options:
(A) Some chemically synthetic substances are not certified organic pesticides.
(B) All chemically synthetic substances are non-organic pesticides.
(C) Some certified organic pesticides are chemically synthetic.
(D) No chemically synthetic substance is a certified organic pesticide.
Answer Key:
C
Step-by-Step Solution & Explanation
In formal logic (Square of Opposition), the universal negative proposition "No S is P" (E-type) and the particular affirmative proposition "Some S is P" (I-type) are strict contradictories. If "No S is P" is true, then "Some S is P" must be false.