Which of the following statement is correct ?
(A) Thorn of Bougainvillea and tendrill of Cucubita show analogy
(B) Homologous organs are pentadactyl organ of man cheetah and whale , they are modified forelimbs
(C) Archaepteryx is modern bird of Mesozoic era
(D) Sweet potato and potato are the example of analogy

Options

A. A, B & D
B. B & D
C. Only C
D. Only B

Answer

To determine which of the statements provided is correct, let's analyze each option step by step:

### Step 1: Analyze Statement A
**Statement A:** Thorn of Bougainvillea and tendril of Cucurbita show analogy.

- **Analysis:** Thorns of Bougainvillea and tendrils of Cucurbita are not analogous; they are actually homologous organs. Both are derived from axillary buds but have different functions: thorns provide protection, while tendrils assist in support. Therefore, this statement is **incorrect**.

### Step 2: Analyze Statement B
**Statement B:** Homologous organs are pentadactyl organ of man, cheetah, and whale; they are modified forelimbs.

- **Analysis:** This statement is correct. The forelimbs of man, cheetah, and whale are indeed homologous organs. They share a common structural framework (pentadactyl structure) but are modified for different functions: grasping in humans, running in cheetahs, and swimming in whales. Thus, this statement is **correct**.

### Step 3: Analyze Statement C
**Statement C:** Archaeopteryx is a modern bird of the Mesozoic era.

- **Analysis:** Archaeopteryx is not a modern bird; it is considered a transitional fossil that exhibits characteristics of both reptiles and birds. It lived during the Mesozoic era but does not represent modern birds. Therefore, this statement is **incorrect**.

### Step 4: Analyze Statement D
**Statement D:** Sweet potato and potato are examples of analogy.

- **Analysis:** Sweet potato (a modified root) and potato (a modified stem) do serve similar functions in food storage, which makes them analogous organs. They have different origins but perform similar functions. Thus, this statement is **correct**.

### Conclusion
The correct statements are:
- **B:** Homologous organs are pentadactyl organs of man, cheetah, and whale; they are modified forelimbs.
- **D:** Sweet potato and potato are examples of analogy.

### Final Answer
The correct statements are B and D.

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