Besides yielding such psychological rewards as relief from stress, deep relaxation, if practiced regularly, can strengthen the immune system and produce a host of other physiological benefits. A . 划线句子 B one can strengthen the immune system through deep relaxation, if it is practiced regularly. C the immune system can be strengthened as a result of deep relaxation if practiced regularly. D when deep relaxation is practiced regularly, the immune system can be strengthened. E When practiced regularly, the results of deep relaxation can be to strengthen the immune system.