Question

If all roses are flowers, and some flowers are red, which of the following must be true?

• A. All roses are red.
• B. Some roses are red.
• C. Some flowers are not roses.
• D. No roses are red.
  \bigskip

Hint:

In critical reasoning questions, focus on what must be true based on the premises, using subset-superset relationships or Venn diagrams to deduce logical conclusions. Avoid options that are only possible.

Answer 1

The Correct Option is C

- Step 1: Break down the premises. The question provides two premises:
- Premise 1: All roses are flowers (roses are a subset of the broader category of flowers).
- Premise 2: Some flowers are red (at least one flower is red).
- Step 2: Analyze logical implications. Since roses are a subset of flowers, the category of flowers is broader, implying there are flowers that are not roses (e.g., tulips, lilies). The fact that some flowers are red does not necessarily involve roses, but it reinforces the broader category of flowers.
- Step 3: Evaluate the options.
- Option (1): "All roses are red" is not guaranteed, as the red flowers may not include roses; the premises do not specify roses' color.
- Option (2): "Some roses are red" is possible but not certain, as the red flowers could be other types of flowers.
- Option (3): "Some flowers are not roses" must be true, as the flower category includes roses and other types, ensuring non-rose flowers exist.
- Option (4): "No roses are red" is not guaranteed, as some roses could be red, contradicting the option.
- Step 4: Confirm with a Venn diagram. Imagine flowers as a large circle with roses as a smaller circle inside it. The larger circle includes other flowers, confirming that some flowers are not roses.
- Step 5: Verify necessity. Option (3) is the only statement that must be true, as the broader flower category necessarily includes non-rose flowers.
- Step 6: Final conclusion. Option (3) Some flowers are not roses is the correct answer, as it logically follows from the premises.
\bigskip