The explanation for this one is pretty simple, no picture necessary. Essentially all of the symbols in the grid are numbers that have been mirrored along a vertical axis. Once you "decode" this pattern you are left with this grid:
2 3 4
5 6 7
7 9 ?
From here the next step is to realize you take the top two rows and add them by column as in:
2 3 4
+ + +
5 6 7 <= View this as (2+5) = 7, (3+6) = 9 and (4+7) = 11.
= = =
7 9 11
This means the answer is 11 and if you flip 11 on it's vertical axis you will end up with three lines as such: | | |
Looking at the possible answers this means the correct answer is (D). Congratulations to IWannaBeAnon for getting the correct answer first, but a point to icey as well for a commendable effort (figuring out the number grid first).
Next puzzle will be up soon, until then well done all!