Which statement is wrong ?

Options

A. Feldspars are not aluminosilicates
B. Beryl is an example of cyclic silicate
C. `Mg_(2) SiO_(4)` is orthosilicate
D. Basic structural unit in silicates `SiO_(4)^(4-)` is the tetrahedron

Answer

To determine which statement is wrong among the given options, we will analyze each statement one by one.

### Step 1: Analyze Statement A
**Statement A:** Feldspars are not aluminum silicates.

- **Explanation:** Feldspars are indeed a group of minerals that are classified as aluminosilicates. They contain aluminum, silicon, and oxygen in their structure. Therefore, this statement is incorrect.

### Step 2: Analyze Statement B
**Statement B:** Beryl is an example of cyclic silicate.

- **Explanation:** Beryl (Be3Al2Si6O18) is indeed classified as a cyclic silicate. It consists of SiO4 tetrahedra that are linked together in a cyclic manner. This statement is correct.

### Step 3: Analyze Statement C
**Statement C:** Mg2SiO4 is orthosilicate.

- **Explanation:** Mg2SiO4 (forsterite) is indeed classified as an orthosilicate. It consists of isolated SiO4 tetrahedra. This statement is also correct.

### Step 4: Analyze Statement D
**Statement D:** Basic structural units of silicate are SiO4 4- tetrahedra.

- **Explanation:** The basic structural unit of silicates is indeed the SiO4 4- tetrahedron. This statement is correct as well.

### Conclusion
After analyzing all the statements, we find that:
- Statement A is the only incorrect statement.

Thus, the answer is:
**The wrong statement is A: Feldspars are not aluminum silicates.**

---