All the hydrides (of group- 16 elements) except one possess reducing property and this character increases  from H2S to H2Te. Identity the hydrides

Among the following, the hydride which is not a reducing agent is H2O. Except H2O all others are reducing agent. The reducing nature of an atom or compound depends on how easily it donates or released electrons.The reducing nature of hydrides increases down the group, so the order is H2O< H2S