$A$ gas decolourises Bayer's reagent but does not react with Tollen's reagent. This gas is:

Which of the following alkyl-substituted alkenes is the most stable?

Ethylene reacts with ..... to form ethylene chlorohydrin.

The product $(C)$ is:

Arrange the following alkenes in decreasing order of stability. Choose the correct answer from the options given below:

Given below are two statements:
Statement-$I$:
$trans$-But-$2$-ene upon treatment with $Br_2$ in $CCl_4$ gives the following product:
(Image provided)
Statement-$II$:
$cis$-But-$2$-ene upon treatment with alkaline $KMnO_4$ gives the following product:
(Image provided)
In the light of the above statements, choose the most appropriate answer from the options given below.