Answer:
由 YUU, YU, YUI, yoshi - reason, cause
言 GEN, GON, i(u), koto - say, speech
キ Katakana "Ki" or The "Tehen" radical - hand
田 DEN, ta - paddy field
糸 SHI, ito - thread
介 KAI - shellfish, be in between
正 SEI, SHOU, tada(shii), masa(ni) - correct, just, exact
召 SHOU, me(su) - summon, wear, take
シ Katakana "Shi" or The "Sanzui" radical - water
及 KYUU, oyo(bu), oyo(bosu) - reach, amount to, match, equal
Pair them like this: 言+正 キ+及 田+介 糸+召 シ+由
証 SHOU - proof
扱 atsuka(u) - handle
界 KAI - world
紹 SHOU - introduction
油 YU, abura - oil