Match the following operating systems and their developing companies
| Operating System | Companies |
| a. Windows operating system | 1. Open source |
| b. Linux | 2. Apple |
| c. OS-X | 3. Microsoft |
| d. Android | 4. Google |
1
a-1, b-2, c-3, d-4
2
a-4, b-1, c-2, d-3
3
a-3, b-1, c-2, d-4
4
a-2, b-3, c-4, d-1