The Answer is C, because:
Well their is so much data that can prove it, that will take at least one hour to enumerate all of them, so I will just write the most obvious one:
You need to calculate the number of identical colors from the start of each symbol until they change.here the pattern: 3|1|3...1|4|2...2|1|4 (each row must be equal to 7)
I have edited my answer after reading this:
"The square layout of the tiles is irrelevant."
So now, the answer is B:
You need to calculate the number of colors switching in each tiles, the pattern is: 1/2/1/1/0/1/1/2/1
Some explanation about how I come to this answer:
First, we need to now what we have here: 6 different colors, 8(+1) tiles, 4 colored circle in each tiles, Only one colored circle can link another one, only one tiles is fully filled with only one color, colors have their own pattern (green + red, orange + blue, yellow + purple), only the (orange + blue) pattern are equal (2 of each of them in their tiles). Now, we can start conceptualizing the pattern by asking some question: does those colored circle linked each others mean we need to read them like this (bottom-left > top-left > top-right > bottom-right) ? If yes, does we can say they are like rainbow ? If yes, RED=1,ORANGE=2,YELLOW=3,GREEN=4,BLUE=5,PURPLE=6 ? If yes, does that mean that each color pattern is equally distanced by 3 (Green = 4 / Red = 1, Orange = 2 / Blue = 5, Yellow = 3 / Purple = 6)? If yes, that mean 3 must be our delimiter for calculating our pattern ? If yes, can we say that we need to read 3 tiles by 3 tiles ? If yes, we can easily see that each of those 3 row of tiles are hugely different in term of colors and number of same colors, right ? If yes, does we will need to read by a logical order following the "arc / rainbow line" ? If yes, that will mean that the type of colors, the color at the start/end and the order of them in the tile is Irrelevant ? If yes, this will indicate that only the colors switching is relevant ? If yes, how can we calculate it ? Maybe, by giving to each tile a point for every color switched, in example: (green,green,green,red = 1) / (orange,blue,blue,orange = 2) / etc.... By this theory, only one symbol can be our next symbol in the pattern: B --Since B is the only tiles with 1pts color switching in those suggested symbol.