Pick out the correct statement

Options

A. By decreasing the temperature pure para-hydrogen can be obtained
B. By increasing the temperature pure ortho-hydrogen can be obtained
C. By decreasing the temperature pure ortho-hydrogen can be obtained
D. By increasing the temperature pure para-hydrogen can be obtained

Answer

A

Explanation

Pure para form can be obtained at low temperature (20K) but pure ortho form is very difficult to obtain.