How many female legislators become representatives for California in 2015?
female legislators refers to gender_bio = 'F'; representatives refers to type = 'rep'; for California refers to state = 'CA'; in 2015 refers to the year of start date is '2015';
SELECT COUNT(*) FROM current AS T1 INNER JOIN `current-terms` AS T2 ON T1.bioguide_id = T2.bioguide WHERE STRFTIME('%Y', T2.start) = '2015' AND T2.state = 'CA' AND T1.gender_bio = 'F'