Which of the following halides is $2^o$?

Write a note on the halogen compounds containing $sp^{3} C - X$ bonds with examples.

Which among the following compounds is a gem-dihalide?

Given below are two statements,one is labeled as Assertion $(A)$ and the other is labeled as Reason $(R)$.
Assertion $(A)$: $CH_2=CH-CH_2-Cl$ is an example of an allyl halide.
Reason $(R)$: Allyl halides are the compounds in which the halogen atom is attached to an $sp^3$ hybridized carbon atom,which is adjacent to a carbon-carbon double bond.
In the light of the two above statements,choose the most appropriate answer from the options given below:

Which of the following compounds is not an allylic halide?

What are vicinal dihalides? Give examples.