A. with modifications, yes it's the hormones let him know you do understand but it's not a good idea especially looking to the Future when people can dig up all sorts of dirt. putting the right spin on it to suit their purpose at the time.

I would choose option a.

Just ignore it. There is nothing shameful or immoral about male sexuality. If you show respect and set a good example as a human being, he can not help but respect you in return, and other women in suite.

The more you tell him not to follow , the more he is likely to rebell against you . I do think you need a mother son relationship between both of you. i am not an expert when it comes to family relationship. i think though instead of focusing on his rights and wrongs choice, take time to be in his world. it can be possible that he needs you and you are somehow not mentally and emotionally available. i am sure if you are , there is nothing but love you see in him.

You could buy him a wife from Russia or Thailand there's loads of adverts on the internet !!!

D) take away his phone. it could be sex predotors.

The first part a C, and the later half of A. That's how I'd handle it.