Which element does not contain any neutrons?

Which of the following processes produces hydrogen with the highest purity $(99.9\%)$?

Calcium cyanamide on treatment with steam under pressure gives ammonia and

Carbogen is

Observe the following reactions:
$I$. $N_{2(g)} + 3H_{2(g)} \xrightarrow[773 \ K, \ 200 \ atm]{X} 2NH_{3(g)}$
$II$. $CO_{(g)} + H_{2}O_{(g)} \xrightarrow[673 \ K]{Y} CO_{2(g)} + H_{2(g)}$
$III$. $CH_{4(g)} + H_{2}O_{(g)} \xrightarrow[1270 \ K]{Z} CO_{(g)} + 3H_{2(g)}$
Catalysts $X$,$Y$,and $Z$ respectively are:

The most dangerous method of preparing hydrogen would be by the action of $HCl$ and