FH←→ is tangent to circle E at point F.
What is the measure of ∠EFH?
80º
90º
160º
180º

Answer: SECOND OPTION.
Step-by-step explanation:
It is important to remember that a tangent to a circle is a line that touches it at one point. This point is called "Point of tangency". By definition, the angle between the tangent and the radius is 90 degrees.
In this case you can observe that EF is the radius of this circle, therefore, the angle between EF and FH measures 90 degrees.
Based on this, you can say the following:
[tex]\angle EFH=90\°[/tex]
This matches with the second option.