Why am i getting asked to do a security code every time i send an email?

every email i send now i have to put in a security code, its taking up time and i dont need it. i will come off of yahoo altogether if this continues.|||ya security code is for ur safety dude.if u type in the safety code correctly nobody lke hackers can view ur mail.Although my yahoo ID does not ask any security code.i wonder why is it asking for yo. anyway it's protecting ur E-mail from others.so don't worry if a little time is wasted okay.it's for ur safety bye.