$L_{1}$ is Regular Language. The first and the last character must be same, and everything in the middle can be absorbed by x.
$L_{2}$ involves a comparison, hence CFL. (DCFL to be precise)
$L_{3}$ involves no comparison. Pretty easy to make a FA of it. Hence, Regular.
Option A
Golden rule
If the language is finite, then regular 100%.
If the language is infinite, but has a "pattern", then regular.
Most of the times, whenever a comparison is involved between two characters, it is CFL. But if we successfully find a "pattern" or a way such that we need not compare, then it'll be Regular. Which is the case with $L_{1}$