Election on the part of the employer shall be made in one of the following ways:
(a) By insuring against liability for compensation, in which case he is deemed, as to all persons employed by him and covered by insurance, to have so elected during the period such insurance remains in force.
(b) By filing with the administrative director a statement to the effect that he accepts the compensation provisions of this division.
(Amended by Stats. 1965, Ch. 1513.)