How to prove these conditions right or wrong?

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enter image description here To solve the questions, I can write easily that

The area of ADC and BDC triangles equal and similarly EBD and CED triangle areas are equal.

From this conditions how to show the following conditions are true or not?

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A. [midpoint theorem]

B. [Equal base and equal altitude]

C. (It is Not necessarily true). When C is obtuse, the foot of the perpendicular from E to AC will lie outside of ⊿ABC. This mean CF is less than 0.5 of AC and AF is then larger than 0.5 of AC. In short, AF > FC. This further implies the claim is not true [according to equal base and equal altitude]. See illustration below.

enter image description here

D. This is not true in general unless AD = DC. Then, AD = DC = DB. This further means angle C must be 90 degrees.

E. This is not true obviously. [Edit: True because area = AC * altitude / 2 = AC * DF.]