效

Right-side rap radical, a hand holding a stick — the indexing radical. It puts 效 in the action / effect family: 教 to teach (strike to instruct), 改 to change, 政 governance. Here it gives the sense of actively producing a result — imitating or carrying out — yielding 'effect, efficacy, to emulate'.

Left 交 supplies the sound — jiāo shifts to xiào through a regular jiao/xiao alternation seen across this phonetic family (校 xiào school, 较 jiào to compare). 交 itself depicts crossed legs, hence the 'crossing' meaning, which here is purely a sound clue.