Read the following statements and select the true ((T)) or false ((F)) statement .
A. The notochord is an ectodermal derived rod-like structure in chordates.
B. Platyhelminthes are triploblastic and pseudocoelomate animals.
C. The alternation of generation in Obelia is called Metagenesis .
D. In ctenophora , only sexual mode of reproduction is observed.

Options

A. `{:(A,B,C,D),(F,F,T,T):}`
B. `{:(A,B,C,D),(T,T,F,F):}`
C. `{:(A,B,C,D),(F,F,F,T):}`
D. `{:(A,B,C,D),(T,F,F,F):}`

Answer

To solve the question, we will analyze each statement one by one and determine whether they are true (T) or false (F).

### Step 1: Analyze Statement A
**Statement A:** The notochord is an ectodermal derived rod-like structure in chordates.
- **Analysis:** The notochord is actually derived from the mesoderm, not the ectoderm. Therefore, this statement is **False (F)**.

### Step 2: Analyze Statement B
**Statement B:** Platyhelminthes are triploblastic and pseudocoelomate animals.
- **Analysis:** Platyhelminthes (flatworms) are actually acoelomate, meaning they do not have a coelom. They are also triploblastic. Therefore, this statement is **False (F)**.

### Step 3: Analyze Statement C
**Statement C:** The alternation of generation in Obelia is called Metagenesis.
- **Analysis:** The term "metagenesis" refers to the alternation of generations, particularly in certain organisms like Obelia, which undergo both sexual and asexual reproduction. Therefore, this statement is **True (T)**.

### Step 4: Analyze Statement D
**Statement D:** In Ctenophora, only sexual mode of reproduction is observed.
- **Analysis:** Ctenophores are known to reproduce both sexually and asexually. Therefore, this statement is **False (F)**.

### Summary of Results
- **Statement A:** False (F)
- **Statement B:** False (F)
- **Statement C:** True (T)
- **Statement D:** False (F)

### Final Answer
The true (T) or false (F) statements are:
- A: F
- B: F
- C: T
- D: F

Thus, the correct answer is:
- A: F
- B: F
- C: T
- D: F

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