The optically active molecule is

Options

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B.
C.
D.

Explanation

To determine which molecule is optically active, we need to understand the criteria for optical activity. An optically active molecule must be chiral, meaning it has no plane of symmetry (POS) and no center of symmetry (CUS). Here’s a step-by-step solution to identify the optically active molecule:

### Step 1: Identify the Molecules
First, we need to look at the given molecules. For this example, let's assume we have three molecules to analyze.

### Step 2: Check for Symmetry
For each molecule, we will check for the presence of a plane of symmetry (POS) and a center of symmetry (CUS).

- **Molecule 1:** Look for any plane that can divide the molecule into two mirror-image halves. If such a plane exists, the molecule is likely not optically active.

- **Molecule 2:** Repeat the process. If you find a plane of symmetry, this molecule is also not optically active.

- **Molecule 3:** Check this molecule as well. If there is no plane of symmetry or center of symmetry, this molecule may be optically active.

### Step 3: Analyze Chirality
Next, we need to determine if any of the molecules are chiral. A chiral molecule must have four different substituents attached to a carbon atom.

- **Molecule 1:** If it has a carbon atom with four different groups, it is chiral.

- **Molecule 2:** Check for chirality as well.

- **Molecule 3:** If this molecule has a chiral center and no symmetry, it is optically active.

### Step 4: Conclusion
After analyzing all three molecules, we conclude which one is optically active based on the absence of symmetry and the presence of chirality.

### Final Answer
The optically active molecule is the one that has no plane of symmetry and is chiral.

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