Option 1 -> "divergent" typically collocates with "from" not "to", making it grammatically incorrect here.
Option 2 -> "diverse" doesn't collocate with "to" and would be grammatically incorrect in this context.
Option 3 -> "discrete" means separate/distinct but doesn't pair with "to" grammatically.
Option 4 -> "dissimilar" correctly collocates with "to" (dissimilar to), and "not dissimilar to" is a double negative meaning "similar to".
Hence, Option 4: dissimilar -> The phrase "not dissimilar to" is a common English expression using a double negative to indicate similarity. The sentence means the carpet-weaving methods in both regions are similar -> correct