we have
Let's Isolate the variable y in each of the cases and then compare with Fiona's equation to determine the solution of the problem
case A)
Multiply by both sides
Divide by both sides
therefore
the case A) is not equal to Fiona's equation
case B)
Multiply by both sides
Divide by both sides
therefore
the case B) is not equal to Fiona's equation
case C)
Multiply by both sides
Divide by both sides
therefore
the case C) is not equal to Fiona's equation
case D)
Multiply by both sides
Divide by both sides
therefore
the case D) is equal to Fiona's equation
<u>the answer is</u>