Please help me to Get rid of spam

[Dr.Haitham]

<font size="3">hello all

how r u ? I hope u r fine ?

please help me to Get rid of spam , i am now using the random question during the registration process but there is no any benefit from it , and there is many annoying arabic and english spam in my forum !!!!!

and i cann't use the activation of the member from E-Mail because my forum is nwe and I hope a larger number of members to register but not spam !!!!!! is there any method or modification can help me ?
my forum version : 3.8.5

thanx 4 all</font>