just chose one correct option for this

Which of the following is not true? 1) A favourable labour efficiency variance could result from using higher quality materials that result in fewer inspections. 2) A favourable labour rate variance could result from lower wage workers quitting. 3) A favourable materials price variance could result from purchasing identical materials from another supplier at a lower price. 4) An unfavourable materials usage variance could result from not efficiently utilising raw materials, thus causing waste