とぼける
とぼける · tobokeru · JLPT N1 · verb-ichidan
to play dumb
Root ぼける = to go dim or dazed; とぼける = pretending to be that dim
ぼける alone means to go blurry or dim-witted. とぼける is the deliberate version: someone who knows the answer but acts clueless. Use it for feigned innocence or a blank face.