What is ture for mammalia:

Options

A. Platypus is oviparous
B. Bats have feather
C. Elephant is a ovo viviparous
D. Diaphragm is absent in them

Answer

To solve the question "What is true for Mammalia?" we need to evaluate each of the given options regarding their accuracy in relation to the characteristics of mammals.

**Step 1: Analyze Option A - Platypus is oviparous.**
- The platypus is indeed an exception among mammals as it lays eggs (oviparous). This statement is true.

**Step 2: Analyze Option B - Bats have feathers.**
- Bats are mammals and have fur, not feathers. This statement is false.

**Step 3: Analyze Option C - Elephant is oviparous.**
- Elephants are viviparous, meaning they give birth to live young, not lay eggs. This statement is false.

**Step 4: Analyze Option D - Diaphragm is absent in them.**
- Mammals, including elephants, have a diaphragm that aids in respiration. This statement is false.

**Conclusion:**
After evaluating all the options, the only true statement regarding Mammalia is:
**Option A: Platypus is oviparous.**

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