In the human resources strategy, compared with internal recruitment, the following options belong to the advantages of external recruitment ().

Enterprises adopting internal recruitment policy have the following advantages: ① upgrading existing employees can mobilize their enthusiasm, cultivate their loyalty, stimulate their enthusiasm for work and help stimulate their overall morale; (2) Using the information and data held by the existing employees to judge whether the candidate is suitable for the job more accurately; (3) It can save a lot of time and expenses in recruitment and selection; ④ If training is needed after recruitment, employees recruited internally can adapt to the training requirements more quickly. Options b and c are the advantages of internal recruitment, and options a and d are correct.