If Star A has optical magnitude of 2 and Star B has optical magnitude of 4, then

1. Star A is twice as bright as Star B
   
2. Star B is twice as bright as Star A
   
3. Star A is about 4 times as bright as Star B
   
4. Star B is about 4 times as bright as Star A
   
5. Star A is about 6 times as bright as Star B
   
6. Star B is about 6 times as bright as Star A