remember
you when you put a negative inside the square root signs, it is complex and undifined
find which values you can use
x+3
what values make it 0? (the boundary between negative and possivie)
x+3=0
x=-3
has to be more than or equal to 0 (because √0=0)
x>-3
2nd one
1-x=0
1-x>0
add x both sides
1>x
so
x>-3 and 1>x
1>x and x>-3
1>x>-3
-3<x<1
B is answer