Answer:
Option B. ∠EFD = 35°
Step-by-step explanation:
In a circle F, it has been given mED = mDB = mBC
We have to find the measure of ∠EFD
We should always remember the inscribed angle theorem which states that the measure of an inscribed angle is always half the measure of intercepted arc.
m(arc BC) = 2×∠CAB = 2×35 = 70°
Now it has been given in the question
mED = mBC
Therefore m(arc ED) = 70°
Again applying the same theorem
m(arc ED) = 2×∠EFD
70° = 2×∠EFD
m∠EFD = 
Option B. 35° is the answer.