The maximum number of `90^(@)` angles between bp-bp of electrons is observed in .

Options

A. `sp^(3)` d hybridisation
B. `dsp^(3)` hybridisation
C. `dsp^(2)` hybridisation
D. `sp^(3) d^(2)` hybridisation

Explanation

To determine the maximum number of 90-degree angles between bond pairs (bp-bp) of electrons, we will analyze the hybridization and molecular geometry of the given options.

### Step 1: Identify the Hybridization
The question mentions the hybridization states, so we need to identify them. The common hybridizations to consider are:
- sp
- sp²
- sp³
- sp³d
- sp³d²

### Step 2: Analyze sp³d Hybridization
For sp³d hybridization, the molecular geometry is typically trigonal bipyramidal. In this geometry:
- There are five bond pairs (AX₅).
- The arrangement consists of three equatorial positions in one plane and two axial positions above and below this plane.

### Step 3: Count the 90-Degree Angles
In the trigonal bipyramidal structure:
- The equatorial bonds are 120 degrees apart from each other.
- The axial bonds are perpendicular (90 degrees) to the equatorial plane.

The 90-degree angles can be counted as follows:
- Each axial bond forms a 90-degree angle with the three equatorial bonds.
- Therefore, for each of the two axial bonds, there are three 90-degree angles.

Thus, the total number of 90-degree angles is:
- 2 axial bonds × 3 equatorial bonds = 6 angles.

### Conclusion
The maximum number of 90-degree angles between bond pairs (bp-bp) of electrons is observed in sp³d hybridization, resulting in a total of 6 angles.