LG G3100 User Manual page 158

You can set the menu relevant to a call by pressing [Select] in
Setting menu.
If you select this menu, you can receive a call by pressing any key
E
except key.
If you select this menu, you can receive an incoming call by only
S
pressing key.
•
If you want to use the handsfree portable(earphone), please
press the button # for a long time after inserting it to the
connector when incoming a call.
If you select this, you can send your phone number to the other
party. That is, your phone number will be displayed on receiver's
phone.
If you select this, you can't send your phone number.
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