Which gas has a pungent and suffocating odor?

Given below are two statements $:$
Statement $I : H_2Se$ is more acidic than $H_2Te$.
Statement $II : H_2Se$ has higher bond enthalpy for dissociation than $H_2Te$.
In the light of the above statements,choose the correct answer from the options given below.

Write the order of thermal stability of the hydrides of Group $16$ elements.

Which of the following acids contains an $O-O$ bond?

What is the abundance of sulfur in the Earth's crust?

Which among the following $P$-block elements forms a colourless and odourless hydride?