please explain why the information is not enough for this question

Tub Co. uses a standard cost system. The following information pertains to direct labor for Product B for the month of October Actual rate paid P8.40 per hour Standard rate P8,00 per hour Standard hours allowed for actual production 2,000 hours Labor efficiency variance P1.600 unfavorable Using the two-way analysis of overhead variances, what is the controllable variance for January? - a. P 3,000 favorable b. P 5,000 favorable c. P 9,000 favorable d. P 10,500 unfavorable Tub Co. uses a standard cost system. The following information pertains to direct labor for Product B for the month of October Actual rate paid P8.40 per hour Standard rate P8,00 per hour Standard hours allowed for actual production 2,000 hours Labor efficiency variance P1.600 unfavorable Using the two-way analysis of overhead variances, what is the controllable variance for January? - a. P 3,000 favorable b. P 5,000 favorable c. P 9,000 favorable d. P 10,500 unfavorable