Which one of the following statements is not true regarding `( +)` Lactose ?

Options

A. On hydrolysis , (+)lactose gives equal amount of D(+) glucose and D(+) galactose .
B. (+) Lactose is a `beta`-glucoside formed by the union of a molecule of D(+) glucose and a molecule of D(+) galactose.
C. (+) Lactose is a reducing sugar and does not exhibit mutarotation .
D. (+) Lactose ,`C_(12)H_(22)O_(11)` contains 8-OH groups.

Explanation

To determine which statement is not true regarding (+) Lactose, we will analyze each statement step by step.

### Step 1: Understand the structure of Lactose
Lactose is a disaccharide composed of two monosaccharides: D-glucose and D-galactose. Its chemical formula is C12H22O11. The structure of lactose can be represented as follows:

- D-glucose: C6H12O6
- D-galactose: C6H12O6

Lactose is formed by a glycosidic bond between the two monosaccharides.

### Step 2: Analyze the statements
1. **Statement 1:** On hydrolysis, lactose gives D-glucose and D-galactose.
- This statement is true. Hydrolysis of lactose in the presence of water breaks it down into its constituent monosaccharides, D-glucose and D-galactose.

2. **Statement 2:** (+) Lactose is a beta glucoside formed by the union of a molecule of D-glucose and a molecule of D-galactose.
- This statement is also true. Lactose is indeed a beta-glucoside formed from D-glucose and D-galactose.

3. **Statement 3:** (+) Lactose is a reducing sugar and does not exhibit mutarotation.
- This statement is not true. Lactose is a reducing sugar, and reducing sugars do exhibit mutarotation due to the presence of a free aldehyde or ketone group that can interconvert between different anomeric forms.

4. **Statement 4:** (+) Lactose contains 8 OH groups.
- This statement is true. The structure of lactose indeed contains 8 hydroxyl (OH) groups.

### Conclusion
The statement that is not true regarding (+) Lactose is **Statement 3**, which claims that lactose does not exhibit mutarotation.

### Final Answer
**The statement that is not true regarding (+) Lactose is: (+) Lactose is a reducing sugar and does not exhibit mutarotation.**

---