Dilute sodium hydroxide does not react with which of the following?

Regarding the hydrides of group $15$ elements $EH_{3}$ $(E = N, P, As, Sb, Bi)$, select the correct statement from the following:
$A$. The stability of hydrides decreases down the group.
$B$. The basicity of hydrides decreases down the group.
$C$. The reducing character increases down the group.
$D$. The boiling point increases down the group.
Choose the correct answer from the options given below:

What are the products obtained when ammonia is reacted with excess chlorine?

What are the products formed when ammonia reacts with excess chlorine?

$Cu +$ conc. $HNO_3$ (hot) $\rightarrow Cu(NO_3)_2 + X$ (oxide of nitrogen);
then $X$ is

Give the preparation of phosphine $(PH_{3})$. State the physical and chemical properties of phosphine $(PH_{3})$. State the uses of phosphine.